ORA-63300
Transaction is automatically rolled back since it is blocking a higher priority transaction from another session.
Cause
This transaction was holding a row lock that blocked a higher priority transaction from another session. The blocked transaction has rolled back this transaction after waiting for the configured target wait time (using PRIORITY_TXNS_HIGH_WAIT_TARGET or PRIORITY_TXNS_MEDIUM_WAIT_TARGET).
Action
User must issue ROLLBACK SQL to the current transaction to acknowledge that they know that the current transaction has been automatically rolled back. Issue ROLLBACK for the local transaction and issue XA_END and XA_ROLLBACK for the XA transaction.