Teradata Parallel Transporter (TPT) is a Teradata tool for Extraction Transformation and Loading. It offers a native, scalable and parallel way of loading the Teradata database.
TPT scripts run in two subsequent phases – Acquisition and Application phase. In the acquisition phase, data are delivered to their designated AMPs. They are sorted during the application phase based on row hash sequence and persisted to disk.
It might happen sometimes a TPT process fails or gets interrupted leaving a lock on the target table. Therefore, when TPT gets restarted, one receives the 2574 error.
One way around this is dropping and recreating the locked table, or releasing the lock manually using the RELEASE MLOAD command. Depending on the phase the load gets interrupted, one uses the RELEASE command with/without the IN APPLY parameter:
/* Acquisition phase */
RELEASE MLOAD databasename.tablename;
/* Application phase */
RELEASE MLOAD databasename.tablename IN APPLY;
Additional information: Teradata Documentation