Time Zone cannot be changed

[Eiion]

1. The reply of the bot says to change time zone using
   ´´´
   /settings timzone
   ´´´
   in oder to change time zone of the server. This does not work.

2. Inside
   ´´´
   /settings
   ´´´
   timezone can be changed with buttons. This does not work.
   But at least with that settings you can change time to UTC.
   What doesn't work is to set time to timezone with the "Server Timezone" button. The reply I get with this method is
   ´´´
   This interaction failed
   ´´´

Trying to change timeszone manually with

/settings timezone UTC+01

or

/settings timezone UTC0100

also does not work.

Either the bot is broken or the instructions are incorrect. Please fix/help.