Hi everyone, new to the forum. I have a 2013 A1 sportback on which I'm trying to replace the pads/discs. Using the correct tool I rewound the piston but it hasnt retracted fully. About 1cm still proud I get the feel like its come off a thread and the piston just spins. I can wind it back out successfully. The piston isn not retracting far enough to get the pads in place. I've done this job on a Polo and this A1 before so I dont think Ive dome anything the wrong way Any suggestions or am I looking at a new caliper.