Failed to initialize Microsoft mail client since generating of access authentication token failed

Question

Our automated JIRA mail handler was working fine yesterday, it created JIRA tickets automatically.  Today (6/21/2023) it stopped working.  When I tested the mail handlers, I get an error "Failed to initialize Microsoft mail client since generating of access authentication token failed." The emails are being routed appropriately and I can see them in the proper email account inbox. How can I fix this?

Lauren Collins_bzt3yg · Answer

Ours has not magically started working again, I've raised a call with Atlassian, will share response once I get one

UPDATE:

Resolved: Reauthorize the mail handler by checking incoming mail settings through Jira Settings > System > Incoming Mail  as shown in below screenshot

Desiree_Anson · Answer

End result, worked with Atlassian, nothing changed on their end or ours, this finally started working again after about 4 or 5 days.  Very inconvenient.