Invite into a shared group results in error message

A friend and I were trying to invite ourselves into a shared group and experienced the following issue:

• creating a group worked properly

• inviting the other one to observe the group works properly as well

• inviting to join the group for sharing live data results in an error message (something went wrong. Try again and contact support.)

We tried this with different groups on different platforms (Android, iOS, Win11) and different browsers as well as the app with exactly the same result.