This is a general issue with Exchange Online accounts because Microsoft enforced a policy that disables Basic Authentication.

Users that use the Exchange Account option from the accounts setup screen will receive this error (or something very similar).

In January 2023 Microsoft will shut down this way of authentication and it would be impossible for the users to log in from the Aqua Mail Exchange Account option with Exchange Online. 

Logging into Exchange Online should be done through the "Office365 option", where it is possible to use Modern Authentication instead of Basic.

Local servers (not online) should not have this issue.