GMail Add-on error: Something went wrong when executing the add-on.

[sz7i]

My colleagues often complain that they see the error from the subject when using Odoo GMail Plugin.

I'm an admin and have built the plugin manually for Odoo on-premise installation. In Google's Log Explorer I can find error messages that might be related

"message": "Access _handleActionCalldenied: : Expired access token.\n at unknown function\n at onCreateLead(main:1406)\n at (main:1283)\n"

Any idea on how to fix this?