I found an event group where the “Test” name comes from. I am not sure why it take is.
I can delete it and see what will happen, but I decided to write here first.
Actually it was some kind of conflict with Polylang plugin. When I turned it off, all the files show. Guess it is with the files translations and associations.
I disabled the “Use Check in/Check out”, “Use hours” is enabled. “Use start/finish hours” is disabled. This means customers can only book one hour inteval from prepared, but i still see “Check out”.