Google Calendar integration now completely broken/blocked

I have been requesting that the connection to Google calendar be fixed for a couple of months as it regularly disconnects. 

Now it has stopped completely with the following message when you try to reconnect it.

"This app is blocked
This app tried to access sensitive info in your Google Account. To keep your account safe, Google blocked this access."

The scheduling of tasks is THE core function of this system. Please make fixing this a higher priority and please communicate on its progress more regularly.