Rear brake lines failed

I took the car for repairs. They replaced the lines and bled the system. Drove the car home, realized the front driver wheel was smoking when I got back. Rim was also too hot to touch as compared to the other wheels. Took the wheel off, tried to compress the brake caliper with a c-clamp and part of the metal piston broke and the caliper did not move. What should I do to fix this? I have a little bit of experience replacing brake pads, calipers, rotors, master cylinders, and bleeding lines. Want to know the best way to approach this problem.