La llave no entra en la cerradura.
CHIA-ve — dos sílabas, acento en la primera.
Comunica inmediatamente si la llave no funciona — no fuerces la cerradura.
'Non entra nella serratura' = does not go into the lock. 'Serratura' = lock. 'Chiave' = key. This can happen if the wrong key is used, the key is inserted upside down, or the lock is faulty. Always describe the exact symptom to help the host diagnose remotely.
La chiave gira ma la porta non si apre.
The key turns but the door does not open.
A different failure mode — the bolt may be stuck
Non riesco ad aprire la porta. Cosa faccio?
I cannot open the door. What should I do?
A general distress call if no specific problem is identified
Sto usando la chiave giusta?
Am I using the right key?
Ask if there are multiple keys and you may be using the wrong one
Las cerraduras italianas antiguas pueden ser delicadas. Si la llave no entra, prueba a girarla ligeramente mientras empujas la puerta. Si no funciona, llama al anfitrión — puede ser un problema del cilindro que necesita un cerrajero.