diff --git a/app/ocpp_proto/chargepoint.py b/app/ocpp_proto/chargepoint.py
index c529f42..d41b857 100644
--- a/app/ocpp_proto/chargepoint.py
+++ b/app/ocpp_proto/chargepoint.py
@@ -176,7 +176,7 @@ class ChargePoint(cp):
                 )
                 if "id_token" in kwargs.keys():
                     if id_token_info.status == AuthorizationStatusType.accepted:
-                        transaction.user_id = UUID(token_owner_id)
+                        transaction.user_id = token_owner_id
                 db.add(transaction)                
             elif event_type == str(TransactionEventType.updated):
                 transaction = db.get(DbTransaction, transaction_info["transaction_id"])
@@ -202,7 +202,7 @@ class ChargePoint(cp):
                             db.add(db_meter_value)
                 if "id_token" in kwargs.keys():
                     if id_token_info.status == AuthorizationStatusType.accepted:
-                        transaction.user_id = UUID(token_owner_id)
+                        transaction.user_id = token_owner_id
             elif event_type == str(TransactionEventType.ended):
                 transaction = db.get(DbTransaction, transaction_info["transaction_id"])
                 transaction.status = TransactionStatus.ENDED
@@ -220,7 +220,7 @@ class ChargePoint(cp):
                 transaction.meter_end = meter_end
                 if "id_token" in kwargs.keys():
                     if id_token_info.status == AuthorizationStatusType.accepted:
-                        transaction.user_id = UUID(token_owner_id)
+                        transaction.user_id = token_owner_id
             db.commit()
 
         if "id_token" in kwargs.keys():