diff --git a/packages/dapi/lib/externalApis/tenderdash/requestTenderRpc.js b/packages/dapi/lib/externalApis/tenderdash/requestTenderRpc.js
new file mode 100644
index 0000000000..efdec5962f
--- /dev/null
+++ b/packages/dapi/lib/externalApis/tenderdash/requestTenderRpc.js
@@ -0,0 +1,55 @@
+const UnavailableGrpcError = require('@dashevo/grpc-common/lib/server/error/UnavailableGrpcError');
+const ResourceExhaustedGrpcError = require('@dashevo/grpc-common/lib/server/error/ResourceExhaustedGrpcError');
+const RPCError = require('../../rpcServer/RPCError');
+
+/**
+ * @param {jaysonClient} rpcClient
+ * @return {requestTenderRpc} A function to make RPC requests to Tenderdash.
+ */
+function requestTenderRpcFactory(rpcClient) {
+  /**
+   * @function
+   * @typedef requestTenderRpc
+   * @param {string} uri
+   * @param {Object} [params={}]
+   * @return {Promise<Object>}
+   */
+  async function requestTenderRpc(uri, params = {}) {
+    let response;
+    try {
+      response = await rpcClient.request(uri, params);
+    } catch (e) {
+      if (e.code === 'ECONNRESET' || e.message === 'socket hang up') {
+        throw new UnavailableGrpcError('Tenderdash is not available');
+      }
+
+      throw new RPCError(
+        e.code || -32602,
+        `Failed to request ${uri}: ${e.message}`,
+        e,
+      );
+    }
+
+    const { result, error: jsonRpcError } = response;
+
+    if (jsonRpcError) {
+      if (typeof jsonRpcError.data === 'string') {
+        if (jsonRpcError.data.includes('too_many_resets')) {
+          throw new ResourceExhaustedGrpcError('tenderdash is not responding: too many requests');
+        }
+      }
+
+      throw new RPCError(
+        jsonRpcError.code || -32602,
+        jsonRpcError.message || 'Internal error',
+        jsonRpcError.data,
+      );
+    }
+
+    return result;
+  }
+
+  return requestTenderRpc;
+}
+
+module.exports = requestTenderRpcFactory;
diff --git a/packages/dapi/lib/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.js b/packages/dapi/lib/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.js
index ad77276042..a17d496918 100644
--- a/packages/dapi/lib/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.js
+++ b/packages/dapi/lib/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.js
@@ -2,9 +2,10 @@ const {
   server: {
     error: {
       InvalidArgumentGrpcError,
-      AlreadyExistsGrpcError,
       ResourceExhaustedGrpcError,
       UnavailableGrpcError,
+      AlreadyExistsGrpcError,
+      InternalGrpcError,
     },
   },
 } = require('@dashevo/grpc-common');
@@ -14,15 +15,23 @@ const {
     BroadcastStateTransitionResponse,
   },
 } = require('@dashevo/dapi-grpc');
+
+const crypto = require('crypto');
+
 const logger = require('../../../logger');
 
 /**
  * @param {jaysonClient} rpcClient
  * @param {createGrpcErrorFromDriveResponse} createGrpcErrorFromDriveResponse
+ * @param {requestTenderRpc} requestTenderRpc
  *
  * @returns {broadcastStateTransitionHandler}
  */
-function broadcastStateTransitionHandlerFactory(rpcClient, createGrpcErrorFromDriveResponse) {
+function broadcastStateTransitionHandlerFactory(
+  rpcClient,
+  createGrpcErrorFromDriveResponse,
+  requestTenderRpc,
+) {
   /**
    * @typedef broadcastStateTransitionHandler
    *
@@ -38,7 +47,9 @@ function broadcastStateTransitionHandlerFactory(rpcClient, createGrpcErrorFromDr
       throw new InvalidArgumentGrpcError('State Transition is not specified');
     }
 
-    const tx = Buffer.from(stByteArray)
+    const stBytes = Buffer.from(stByteArray);
+
+    const tx = stBytes
       .toString('base64');
 
     let response;
@@ -46,7 +57,7 @@ function broadcastStateTransitionHandlerFactory(rpcClient, createGrpcErrorFromDr
     try {
       response = await rpcClient.request('broadcast_tx', { tx });
     } catch (e) {
-      if (e.message === 'socket hang up') {
+      if (e.code === 'ECONNRESET' || e.message === 'socket hang up') {
         throw new UnavailableGrpcError('Tenderdash is not available');
       }
 
@@ -55,15 +66,65 @@ function broadcastStateTransitionHandlerFactory(rpcClient, createGrpcErrorFromDr
       throw e;
     }
 
-    const {
-      result,
-      error: jsonRpcError,
-    } = response;
+    const { result, error: jsonRpcError } = response;
 
     if (jsonRpcError) {
       if (typeof jsonRpcError.data === 'string') {
         if (jsonRpcError.data === 'tx already exists in cache') {
-          throw new AlreadyExistsGrpcError('state transition already in chain');
+          // We need to figure out and report to user why the ST cached
+          const stHash = crypto.createHash('sha256')
+            .update(stBytes)
+            .digest();
+
+          // TODO: Apply search filter to fetch specific state transition
+          // Throw an already exist in mempool error if the ST in mempool
+          const unconfirmedTxsResponse = await requestTenderRpc('unconfirmed_txs', { limit: 100 });
+
+          if (unconfirmedTxsResponse?.txs?.includes(stBytes.toString('base64'))) {
+            throw new AlreadyExistsGrpcError('state transition already in mempool');
+          }
+
+          // Throw an already exist in chain error if the ST is committed
+          let txResponse;
+          try {
+            txResponse = await requestTenderRpc('tx', { hash: stHash.toString('base64') });
+          } catch (e) {
+            if (typeof e.data !== 'string' || !e.data.includes('not found')) {
+              throw e;
+            }
+          }
+
+          if (txResponse?.tx_result) {
+            throw new AlreadyExistsGrpcError('state transition already in chain');
+          }
+
+          // If the ST not in mempool and not in the state but still in the cache
+          // it means it was invalidated by CheckTx so we run CheckTx again to provide
+          // the validation error
+          const checkTxResponse = await requestTenderRpc('check_tx', { tx });
+
+          if (checkTxResponse?.code !== 0) {
+            // Return validation error
+            throw await createGrpcErrorFromDriveResponse(
+              checkTxResponse.code,
+              checkTxResponse.info,
+            );
+          } else {
+            // CheckTx passes for the ST, it means we have a bug in Drive so ST is passing check
+            // tx and then removed from the block. The removal from the block doesn't remove ST
+            // from the cache because it's happening only one proposer and other nodes do not know
+            // that this ST was processed and keep it in the cache
+            // The best what we can do is to return an internal error and and log the transaction
+            logger.warn({
+              tx,
+            }, `State transition ${stHash.toString('hex')} is passing CheckTx but removed from the block by proposal`);
+
+            const error = new Error('State Transition processing error. Please report'
+              + ' faulty state transition and try to create a new state transition with different'
+              + ' hash as a workaround.');
+
+            throw new InternalGrpcError(error);
+          }
         }
 
         if (jsonRpcError.data.startsWith('Tx too large.')) {
diff --git a/packages/dapi/lib/grpcServer/handlers/platform/platformHandlersFactory.js b/packages/dapi/lib/grpcServer/handlers/platform/platformHandlersFactory.js
index 641071d357..8288583ab7 100644
--- a/packages/dapi/lib/grpcServer/handlers/platform/platformHandlersFactory.js
+++ b/packages/dapi/lib/grpcServer/handlers/platform/platformHandlersFactory.js
@@ -55,6 +55,7 @@ const waitForTransactionToBeProvableFactory = require('../../../externalApis/ten
 const waitForTransactionResult = require('../../../externalApis/tenderdash/waitForTransactionToBeProvable/waitForTransactionResult');
 const getExistingTransactionResultFactory = require('../../../externalApis/tenderdash/waitForTransactionToBeProvable/getExistingTransactionResult');
 const getConsensusParamsFactory = require('../../../externalApis/tenderdash/getConsensusParamsFactory');
+const requestTenderRpcFactory = require('../../../externalApis/tenderdash/requestTenderRpc');
 
 /**
  * @param {jaysonClient} rpcClient
@@ -73,10 +74,13 @@ function platformHandlersFactory(
 ) {
   const wrapInErrorHandler = wrapInErrorHandlerFactory(logger, isProductionEnvironment);
 
+  const requestTenderRpc = requestTenderRpcFactory(rpcClient);
+
   // broadcastStateTransition
   const broadcastStateTransitionHandler = broadcastStateTransitionHandlerFactory(
     rpcClient,
     createGrpcErrorFromDriveResponse,
+    requestTenderRpc,
   );
 
   const wrappedBroadcastStateTransition = jsonToProtobufHandlerWrapper(
diff --git a/packages/dapi/test/unit/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.spec.js b/packages/dapi/test/unit/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.spec.js
index 3dc61b2eb4..de1152d015 100644
--- a/packages/dapi/test/unit/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.spec.js
+++ b/packages/dapi/test/unit/grpcServer/handlers/platform/broadcastStateTransitionHandlerFactory.spec.js
@@ -5,6 +5,7 @@ const {
       AlreadyExistsGrpcError,
       UnavailableGrpcError,
       ResourceExhaustedGrpcError,
+      InternalGrpcError,
     },
   },
 } = require('@dashevo/grpc-common');
@@ -36,6 +37,7 @@ describe('broadcastStateTransitionHandlerFactory', () => {
   let log;
   let code;
   let createGrpcErrorFromDriveResponseMock;
+  let requestTenderRpcMock;
 
   before(async () => {
     await loadWasmDpp();
@@ -82,11 +84,14 @@ describe('broadcastStateTransitionHandlerFactory', () => {
       request: this.sinon.stub().resolves(response),
     };
 
+    requestTenderRpcMock = this.sinon.stub();
+
     createGrpcErrorFromDriveResponseMock = this.sinon.stub();
 
     broadcastStateTransitionHandler = broadcastStateTransitionHandlerFactory(
       rpcClientMock,
       createGrpcErrorFromDriveResponseMock,
+      requestTenderRpcMock,
     );
   });
 
@@ -182,13 +187,38 @@ describe('broadcastStateTransitionHandlerFactory', () => {
     }
   });
 
-  it('should throw AlreadyExistsGrpcError if transaction was broadcasted twice', async () => {
+  it('should throw AlreadyExistsGrpcError if transaction in mempool', async () => {
+    response.error = {
+      code: -32603,
+      message: 'Internal error',
+      data: 'tx already exists in cache',
+    };
+
+    requestTenderRpcMock.withArgs('unconfirmed_txs').resolves({
+      txs: [stateTransitionFixture.toBuffer().toString('base64')],
+    });
+
+    try {
+      await broadcastStateTransitionHandler(call);
+
+      expect.fail('should throw AlreadyExistsGrpcError');
+    } catch (e) {
+      expect(e).to.be.an.instanceOf(AlreadyExistsGrpcError);
+      expect(e.getMessage()).to.equal('state transition already in mempool');
+    }
+  });
+
+  it('should throw AlreadyExistsGrpcError if transaction in chain', async () => {
     response.error = {
       code: -32603,
       message: 'Internal error',
       data: 'tx already exists in cache',
     };
 
+    requestTenderRpcMock.withArgs('tx').resolves({
+      tx_result: { },
+    });
+
     try {
       await broadcastStateTransitionHandler(call);
 
@@ -199,6 +229,52 @@ describe('broadcastStateTransitionHandlerFactory', () => {
     }
   });
 
+  it('should throw consensus result for invalid transition in cache', async () => {
+    response.error = {
+      code: -32603,
+      message: 'Internal error',
+      data: 'tx already exists in cache',
+    };
+
+    requestTenderRpcMock.withArgs('check_tx').resolves({
+      code: 1,
+      info: 'some info',
+    });
+
+    const error = new Error('some error');
+
+    createGrpcErrorFromDriveResponseMock.resolves(error);
+
+    try {
+      await broadcastStateTransitionHandler(call);
+
+      expect.fail('should throw consensus error');
+    } catch (e) {
+      expect(e).to.equal(error);
+    }
+  });
+
+  it('should throw internal error for transition in cache that passing check tx', async () => {
+    response.error = {
+      code: -32603,
+      message: 'Internal error',
+      data: 'tx already exists in cache',
+    };
+
+    requestTenderRpcMock.withArgs('check_tx').resolves({
+      code: 0,
+    });
+
+    try {
+      await broadcastStateTransitionHandler(call);
+
+      expect.fail('should throw InternalError');
+    } catch (e) {
+      expect(e).to.be.an.instanceOf(InternalGrpcError);
+      expect(e.getMessage()).to.equal('Internal error');
+    }
+  });
+
   it('should throw a gRPC error based on drive\'s response', async () => {
     const message = 'not found';
     const metadata = {