diff --git a/arnold/models/database/sample.py b/arnold/models/database/sample.py
index d16172b..01ec28c 100644
--- a/arnold/models/database/sample.py
+++ b/arnold/models/database/sample.py
@@ -71,4 +71,4 @@ def set_id(cls, v, values: dict) -> str:
         return values.get("sample_id")
 
     class Config:
-        allow_population_by_field_name = True
+        populate_by_name = True
diff --git a/arnold/models/database/step.py b/arnold/models/database/step.py
index 0a314c9..fffeadd 100644
--- a/arnold/models/database/step.py
+++ b/arnold/models/database/step.py
@@ -27,5 +27,5 @@ class Step(BaseModel):
     process_udfs: Optional[dict] = {}
 
     class Config:
-        allow_population_by_field_name = True
+        populate_by_name = True
         extra = Extra.allow
diff --git a/tests/conftest.py b/tests/conftest.py
index 5ee907e..a8dfe02 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -54,14 +54,14 @@ def valid_step():
 
 @pytest.fixture(scope="function")
 def valid_sample():
-    return Sample(sample_id="some_sample_id", _id="some_id")
+    return Sample(sample_id="some_sample_id", id="some_id")
 
 
 @pytest.fixture(scope="function")
 def valid_samples():
     return [
-        Sample(sample_id="some_sample_id", _id="some_id").model_dump(by_alias=True),
-        Sample(sample_id="some_other_sample_id", _id="some_other_id").model_dump(by_alias=True),
+        Sample(sample_id="some_sample_id", id="some_id").model_dump(),
+        Sample(sample_id="some_other_sample_id", id="some_other_id").model_dump(),
     ]