Email sync issues on new Macs with M3 chip

Purchased a few MacBook Pro's with M3 chip and we're having issues getting our MS Exchange email accounts to work. It will work for a period of time and then will stop syncing and emails that are sent will sit in the Outbox. We can usually get it working again by removing and re-adding the account. This is an issue in both the latest version of MS Outlook (16.80) and using Apple Mail. Users on the M1 MacBooks using the same Outlook version and Mail app do not have any issues. We're running MS Exchange 2016 on premise. Anyone run into this or have any ideas at all? Users are getting frustrated to say the least :/