My Focus and my old mundano needed the piston rotating back in. I used narrow nosed pliers and it wasn't the easiest but i didn't have the correct tool. Theres a cut out to locate on a block on the back of the pad too.

I'm getting a tool before the next time to save the grief.

takes a bit of effort to get started, try turning the opposite direction then back to get some movement. took ages on one side when i did them on my focus then the other side was a piece of piss!