my cylinder on the back rear drum breaks is always pushed in on both sides where the shoes touch, they dont come out when i apply the breaks what do i need to do to fix this problem?

if not getting fluid to said wheel cylinder, then start with the split off, should be somewhere near the rear differentail, mounted to it or nearby...or if there is fluid getting to it, but the pistons inside are stuck, then a new wheel cylinder and a good bleeding will be required/