Union lock

I was called to a property in south Ockendon by a customer who could not get into his house,the dead bolt was not retracting.I gaind entry to the property checked the cylinder which was fine I then checked the lock case to find that intermittently the lock would not work.The customer informed they had got a temporary lock in it when it went wrong a while ago.i ordered in a new lock case the correct one for the door with I reckon was about 30 years old.  Yesterday I fitted it and tbe customer is happy.