Email sync often stops for users for no reason

Email sync often stops for users for no reason

My users often find that their email sync has stopped seemingly for no reason at random times.

They can go into the Emails section of CRM, see that it is days behind, and manually use the refresh there to get it going again.

Alternatively they are able to go to mail.zoho.com and manually refresh from there.

Has anyone else experienced this? What was your solution?

I've contacted the help desk on several occasions and never had a true fix that has lasted for the users.