We enabled MFA in GP and since then any Purchase Orders that are recalled because they need a change order made to them and resubmitted to the workflow, the approval emails are not being sent. When the workflow manager delegates the PO in GP they are prompted to select their MS account, they select it and then get "An unknown error has occurred". They Hit Ok, the PO goes through the workflow but the approval emails are not sent.
However, any new POs that are created since MFA, email approvals are being sent and received.
Our workflow setup uses Anonymous Authentication and our SMTP server is an outlook.com address.
When I use the Test E-Mail button in the Workflow Setup window, I don't receive an email.