1. Navigate to the site collection where the Collaboration Manager is installed. Open the Collaboration Manager App by clicking site contents and then Collaboration Manager 365 v2.
2. In the Collaboration Manager App click the "Setup"-Button.
3. Then click on "Install Collaboration Manager 365".
4. Then reinstall the Collaboration Manager by clicking the Button.
5. After reinstalling the Collaboration Manager you have to click "Allow modern sites".
Then you have to accept the Graph permissions.
Afterwards you get the following response screen.
The Collaboration Manager 365 is now successfully updated.