A misaligned photo-eye sensor, a dead remote battery, or a disconnected wall switch - those you can check yourself before calling anyone. Unplug the opener, see if the door moves by hand. If it's heavy and won't lift smoothly, that's spring tension doing its job wrong, and that's not a DIY repair.
Torsion springs on doors this size store enough force to break bones or worse if the winding cone slips. We don't recommend homeowners touch spring adjustment, cable replacement, or anything involving the winding bars, full stop. If the door is off its track or the panel is bent, that's also a call-it-in job - forcing a bent track back into place usually just moves the damage to the opener motor next.