K reg, never usually lets me down, but on a couple of occasions it has refused to let the key turn in the barrel. When this happens I have tried the duplicate key, waggled the steering wheel, moved the key in and out, tried it up the other way, applied a little lubricant, turned it gently to the left and right with no luck. Then suddenly while trying it finally turns.
Cant go on like this. Is a replacement barrel the only answer and then will I need two keys, one for the doors and another for the ignition?