@Micha3110 yes, others have reported the same problem. however there has been no fix to date

@sdetweil I did that too (for days), then I get the error message: “Error in the “calendar” module. Check the login files for further details” for one calendar I restarted the Raspberry Pi a few times and now it seems to be working. I don’t know where the error was. Thank you for your time and tips. Greetings Michael