OutGoing Postback Logs
In this page you can check all the postbacks you are sending to your Publishers/Affiliates.
Access this page through Navigation Menu->Logs->Outgoing PostBack Logs
If your postbacks to publisher is failing you cam check why is it failing on this page. Check the Error Status Coded returned by the Publisher’s Postback URL.
Also You May try to resend the postback through This Page: