How can I fix the central locking system in my Audi 80?

My Audi 80 central locking system is not working properly. Whenever I try to lock the car using the key or the central button in the car, the doors do not lock and I need to manually lock each door. What could be causing this issue and how can I fix it?

Start by checking the fuse for the central locking system. If it is blown, replace it with a new one. If that doesn't solve the issue, it could be a malfunctioning actuator or wiring problem. It's best to take it to a mechanic to diagnose and fix the issue.