Hi Gevans,
Please go to Send /Receive, click on the button of Work Offline and see if this can fix the issue:

If the issue persists, please collect the connection status at the right bottom then we can do further research on this.
Hope this can be helpful.
Best regards,
Yuki Sun
Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact
tnsf@microsoft.com.

Click
here to learn more. Visit the dedicated
forum to share, explore and talk to experts about Microsoft Teams.