"Your account could not be synced" - what does it mean?

I received an auto-mail telling me my account has stopped syncing with Qualifier. How I fix it?

If you haven’t been active in a while or if you have changed your password since your last login then Nylas, our email service provider, might lose the connection with the email server, blocking your bot to send out any emails.

To resume activity, just sign in again with your login credentials and it will resume activity.