Safety: Garage doors are heavy and spring/cable systems can be under significant tension. Do not loosen or disassemble high-tension hardware unless you are qualified to do so.
Stop Repeated Operation
An uneven door can bind in the tracks and place additional load on hardware or the opener.
Look for Loose Cables or Rollers
Without touching tensioned parts, note whether a cable appears slack, a roller is outside the track, or one side of the door is visibly lower.
Correct the Cause, Not Just the Angle
Realigning a door requires identifying why it became uneven in the first place.