We have a change in IP at our end and hence asked our partners to adjust the same at their end.
They have confirmed that they are using the new IP now (URL is same) and it is activated on their firewall.(Only one partner has this problem,others can send messages to us using new IP)
Still,they are not able to send anything to us and get 403 forbidden error.
They are able to receive messages from us.
We have confirmed,there is no change in AS2 IDs,Message subjects at their end and XI configuration(sender agreement,etc) at our end.
This scenario used to work fine till we had this IP change at our end.
Kindly let me know what could be wrong ?