No address found for partner function type : 0002 and 0013

Hi Experts,

I have SRM PO and it is partially confirmed ,requester and Goods receipant has left the organisation, now another user trying to post the confirmation, getting the error :

No address found for partner function type : 0002

No address found for partner function type : 0013

We understood that requester and Goods receipant  has left the organisation and this user is not there in organisation structure, hence we are getting the error.

Now we are trying to amend requester and goods receipant  in the PO with new user(alreday there in the Orgn structure) but system is not allowing to do the same.

How can i post the confirmation now?? is ther any way to post the confirmation without amending the PO ?

Thanks in advance

Suresh.A