What was found
MAIN BOARDING DOOR WOULD NOT OPEN. TRIED BOTH INSIDE AND OUTSIDE HANDLES. COULD NOT GET THEM TO BUDGE. MAINTENANCE APPLIED FORCE ON BOTH INSIDE AND OUTSIDE SIMULTANEOUSLY, WHICH RESULTED IN A LOUD, SHARP, BANG, AND THE DOOR OPENING. CLEARED DEBRIS FROM DOOR FRAME AND PERFORMED OPS CHECK OF PASSENGER DOOR IAW AMM 52-11-00. OPS CHECKED GOOD, ACFT OK TO RETURN TO SERVICE.