Why my calendar randomly disconnects?

There can be several reasons for your calendar to disconnect from Sembly without your will. The main reason is an ‘Invalid Grant’ error, which is caused mainly because of a problem with authentication tokens. After having the ‘Invalid Grant’ error, Sembly will disconnect your integration. 

Should such an event occur to your account, we will send a notification to your email. 

Failures, that cause ‘Invalid Grant’ error:

• your google account has been deleted;
• the token has been expired or revoked;

Other reasons are:

• you revoked Sembly's access in Google settings;
• the refresh token has not been used for six months;
• you changed the password in Google account;
• you connected more than 50 apps to Google account after Sembly;
• you belong to a Google Cloud Platform organization that has session control policies in effect.

For more information, read Google article: https://developers.google.com/identity/protocols/oauth2#expiration