diff --git a/flow/connectors/postgres/qrep_query_executor.go b/flow/connectors/postgres/qrep_query_executor.go
index 8c83beeaa5..c7d75c4500 100644
--- a/flow/connectors/postgres/qrep_query_executor.go
+++ b/flow/connectors/postgres/qrep_query_executor.go
@@ -103,12 +103,12 @@ func (qe *QRepQueryExecutor) fieldDescriptionsToSchema(fds []pgconn.FieldDescrip
 		ctype := postgresOIDToQValueKind(fd.DataTypeOID)
 		if ctype == qvalue.QValueKindInvalid {
 			var err error
-			ctype = qvalue.QValueKind(qe.customTypeMap[fd.DataTypeOID])
 			if err != nil {
-				ctype = qvalue.QValueKindInvalid
 				typeName, ok := qe.customTypeMap[fd.DataTypeOID]
 				if ok {
 					ctype = customTypeToQKind(typeName)
+				} else {
+					ctype = qvalue.QValueKindString
 				}
 			}
 		}
diff --git a/flow/model/qvalue/avro_converter.go b/flow/model/qvalue/avro_converter.go
index 9b8db89d78..52aaa87500 100644
--- a/flow/model/qvalue/avro_converter.go
+++ b/flow/model/qvalue/avro_converter.go
@@ -1,7 +1,6 @@
 package qvalue
 
 import (
-	"errors"
 	"fmt"
 	"math/big"
 	"time"
@@ -123,7 +122,7 @@ func GetAvroSchemaFromQValueKind(kind QValueKind, nullable bool) (*QValueKindAvr
 			AvroLogicalSchema: "string",
 		}, nil
 	default:
-		return nil, errors.New("unsupported QValueKind type")
+		return nil, fmt.Errorf("unsupported QValueKind type: %s", kind)
 	}
 }