Exchange email does not load content on mail app in a Mac computer

For the last couple of days now, Exchange email messages do not download to two different desktop computers (iMac and MacBook Pro) using the mail app native to the MacOS. I can see the message in my mail inbox, along with the subject and sender. But no content is loaded. Messages also fail to save when I am drafting a message, and I get this message:

An internal server error occurred. The operation failed. The value is set to null

Parameter name: options.ImceaEncapsulationDomain

In contrast, messages download just fine in Outlook Microsoft365 webmail and on the mail app on my iPhone.

Any suggestion?

Thanks!