Eurocylinders are one of the most common locks fitted to properties today. They are fitted to uPVC, composite, wooden and alumininium doors.
One of the most common faults that I have found with Eurocylinders during my time, is a slipped cam.
The problem with a slipped cam is that the key can't be removed once the door is locked. When this happens the cam is not positioned in the door mechanism correctly, this prevents the lock from rotating fully so the key is in the correct position and can be removed.
I believe that these faults can be due to inferior locks in some cases, but a lot of the time I find the doors are not operating correctly due to poor fitting or having dropped over time and the customer has had to use excess force to lock their door.
I am often told that a door has a particular "knack" to use it. If a door needs a special knack to use then its only a matter of time until you will require the assistance of a locksmith.
If you can accurately explain the problem and the type of lock to a good locksmith they will know what to do before they arrive. If you call Mark he will be more than happy to advise.