Multiple abends in CICS region, IBM reviewed dump and identified that the cause of the abends were the ISER transaction. The ISER transaction is trying to post the same ECB.
The CICS region has a runaway task terminator, hence ISER was getting purged since it exceeded the runaway task time specified.
CA InterTest for CICS maintains a permanent service task that runs under the transaction ID ISER. The ISER transaction will run for the life of CICS and is not a runaway task. The ISER transaction should not be purged by any user or monitoring program.
CICS cannot complete a normal shutdown until this task ends. It is important that you deactivate CA InterTest for CICS before CICS shutdown to terminate the ISER transaction. Adding program IN25PLTE to the CICS shutdown table will purge the ISER transaction at CICS shutdown time.