3830321 - How do I investigate missing Approve and Deny buttons on an approvable document in SAP Ariba Procurement?

A user reports that they cannot act on a document they expect to approve: when they open the approvable document, the Approve and Deny buttons are not available. The user believes they are one of the document's approvers. I need to find out why the buttons are unavailable and restore the user's ability to act on the document.

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