It seems that some “doorbells” are not working. The only ones I know for sure are on Level 7.
If you want to check your own, the easiest way is to go downstairs and ring your own apartment number. If it is working correctly then the light should come on to illuminate the person at the front door. For my apartment the light does NOT come on and the ‘ringing’ does not happen.
The repairman will be here Tuesday to fix