Request to Approve Supplier for Spend is Pending Approval even though it is Approved

Summary:
External supplier registration requests are approved by all the approvers and the BPM task is completed as Approved but it is in Pending approval status in the front end. I have tried to cancel the request, however, as it is showing as approved there are not actions available to take.

When searching for the request in 'Manage Supplier Registration Requests', it shows up as approved.

I've added the duty 'Supplier Registration Management' to my user but this has not changed anything.

Has anyone else experiences this and have a fix?

Thanks!