Concurrent Requests stay in Inactive/No Manager (or) Pending / Standby forever

Concurrent Requests stay in Inactive/No Manager (or) Pending / Standby forever .All the managers are up and running.  But it does not process pick-up any new requests leaving them all the remaining request in hang status. If manager is not processing any requests, there can only be few reasons: 1) Specialization rules prohibits processing any requests (Note 1311526.1) 2) Program with Run alone flag is submitted with pending or running status 3) All the Managers are all busy. 4) Concurrent Program has crashed and managers are still waiting for completion. 5) Concurrent Managers have crashed and somehow not recovered yet . Run the Below query to identify the programs that are Run alone flag enabled. SQL> select request_id from fnd_concurrent_requests where CONCURRENT_PROGRAM_ID in ( SELECT CONCURRENT_PROGRAM_ID FROM FND_CONCURRENT_PROGRAMS_VL WHERE RUN_ALONE_FLAG='Y');  Note : Runalone means exactly what it says. It means that it runs alone, no other requests can be running. That means, if such program runs (with