Create Accounting- Cost Management not processing the events

Hi We recently observed that the Create Accounting program is not processing the Events,

There are eligible events in xla_events and the GL period is also open. but  the program completes normally without spawning the child programs like , accounting program, posting to single ledger..etc..

the only message says " there are no eligible transactions" to Process. its strange Behavior

For Process type "receiving" it works fine but for INV and WIP events its not picking,.

Any ideas please

Thanks,

Krishna