Mail Fetching Issue

Hello, I"m Getting the below mail fetching error, we have not done any changes on mail server or mail server settings:

"Exception while trying to open folder"
"Probabale cause: A3 BAD Request is throttled. Suggested Backoff Time: 40464 milliseconds"

Below are the environment details:

9.4 Build 9419 (Enterprise)
MSSQL
Office365
Incoming: Imaps port 993
Outgoing: SMTP port 587