2004 Toyota Corolla knocking noise in rear when brakes are

The brakes were installed improperly or the drums/rotors are out of round.

Take back to installer, have them check for loose hold downs, broken springs, and if necessary have them turn drums (on rear). Also have front checked for warped rotors, loose caliper bolts, pads installed improperly, caliper slide pins that do not move freely.

Toyota rear drums/front pads are relitively simple compared to other brands.