Hi Dipak,
First of all, there are two types:
1) AO Type = Event Handler Creation
2) Event Type = Posting Events
1a) If you use standard relevance, your PO should have same values which is used in AOT relevance. Other wise it will be false and no EH is created.
2a) If you use standard relevance, your PO should have same values which is used in EVENT TYPE relevance. Other wise it will be false and no EVENTS will be created/posted.
send us AOT screen shots and if you can share, your sample PO EKKO/EKPO.
Thanks,
Vishnu