diff --git a/traffic_monitor/cache/cache_test.go b/traffic_monitor/cache/cache_test.go
index bf4b29b0ca..43b2ad6393 100644
--- a/traffic_monitor/cache/cache_test.go
+++ b/traffic_monitor/cache/cache_test.go
@@ -139,7 +139,7 @@ func TestParseAndDecode(t *testing.T) {
 	if val, ok := miscStats["plugin.system_stats.timestamp_ms_float64"]; ok {
 		valType := reflect.TypeOf(val)
 		if valType.Kind() != reflect.Float64 {
-			t.Errorf("type mismatch, expected: string, got:%s", valType)
+			t.Errorf("type mismatch, expected: float64, got:%s", valType)
 		}
 		val1, _ := parseNumericStat(val)
 		if val1 != uint64(1684784877939) {