Google Calendar SMS Notifications cancelled
SMS notifications for Google Calendar events will be removed January 7, 2019. The notifications will cease to work on that date and instead in-app notifications will be the main method of reminding users of upcoming events. Google has confirmed that users that have the SMS notifications set up will be automatically notified in one of two ways. If a user has Calendar open or the Google Calendar app on a mobile device, they will receive in-app notifications. If a user has SMS notifications set up for new events, changed events, cancelled events or response, they will receive an email. If you have disabled calendar notifications, then head to Settings > Apps & notifications > Find the Calendar app > Turn notifications on. Google also stated that the Calendar API will be updated to reflect this upcoming change. - 9to5Google