when they serviced it or if you serviced it did you they/you inspect the expander ? when you fully apply the handbrake there should be 3 -9 clicks before the handbrake is fully applied, any more then you need to adjust, take out the coin tray at rear of the car, this will expose the adjuster, fully release the handbrake, then undo the adjusting nut several turns so the cable is relaxed.
chock front wheels, jack the rear up onto axle stands, start at the right hand side wheel prise out the blank plug for adjusting the knurled nut, fully expand the handbrake shoes until the drum will not turn, back the knurled nut off by about 5 turns and see if the drum with turn with a little drag, do this to other side, then adjust the cable in the rear of the car, so the handbrake starts to grip at about 3 clicks and fully holds at about 5 clicks but if you pull hard it can reach 7 clicks, remember inside the drum must be in good condition, also clean of dust etc, so cleaning at six month intervals will be your best friend.