The room has not been cleaned.
PU-li-ta — three syllables, stress on the first.
If your room is not cleaned by mid-afternoon, call reception to request housekeeping.
'Non è stata pulita' is the passive voice in passato prossimo: 'non è stata' (has not been) + 'pulita' (cleaned, feminine). This passive construction with 'essere' is standard for stating what has or has not been done to a room.
La camera non è stata rifatta.
The room has not been made up.
'Rifare' refers to making the bed and tidying — the full clean is 'pulire'
Il letto non è stato rifatto.
The bed has not been made.
Specific about the bed rather than the whole room
C'era ancora il cartello 'Non disturbare' sulla porta.
There was still a 'Do not disturb' sign on the door.
This explains why housekeeping may not have entered — remember to remove the sign
In recent years, many Italian hotels have adopted 'green' policies where rooms are cleaned every other day to save water and energy. If this is the policy, you should be informed at check-in. If you prefer daily cleaning, you are entitled to request it.