The connection is lost when the Mautic refresh token is Expires. You only need to change the Access token lifetime i.e 3600 or more and Refresh token lifetime i.e 365 days.
To do this, login to Mautic, click on Setting Tab on the right top corner. Now go to Configuration > API Settings. You’ll find the settings to change the access and refresh token lifetime.
You can also check our APP setup guide to learn how to do it.