Hi Nirav,
I'm not familiar with these ALM BAPIs, but my first guess would be that you need to include the CREATE BAPI within your stateful context! E.g. like this:
1. RfcSessionManager.BeginContext()
2. Invoke CREATE BAPI
3. Invoke SAVE BAPI
4. Invoke BAPI_TRANSACTION_COMMIT
5. RfcSessionManager.EndContext()
Otherwise the Create step and the Save step might run in different user sessions, and then what is the Save step supposed to save... 
Best Regards, Ulrich