Workflow Error in SRM 4.0

Hi everyone,

I have a simple question about SRM,

When I try to edit my PO, system returns with error mesage "Document has still been prossesing in background, please try again later"

I tried to use SWUE with the GUID number of PO, after that the status of PO turns "Waiting for Approval" to "In your basket"

But after that, when i try to change the PO i still encounter the same message "Document has still been prossesing in background"

How can i solve this problem?

Thanks for your interest.