A fair number of these calls are something you can resolve yourself in two minutes, and we will say so on the phone rather than charge you for it.
Try this first
Humming but not turning means the motor is fine and something is jammed. Cut the power, free the flywheel with the hex key that came with the unit, then press the reset button underneath. If it is silent, the reset alone often does it.
Undersized for the kitchen
Builder-grade disposals in large Mount Pleasant kitchens are frequently underpowered for a household that genuinely cooks and entertains. If yours jams on ordinary food waste, the unit is undersized rather than faulty, and upgrading solves it permanently.
When it is actually finished
Water leaking from the body rather than the connections means the housing has corroded through, which is not repairable. Repeated tripping after a reset points to a failing motor.
The grease it does not handle
A disposal grinds solids but does nothing about fats, which cool and coat the line. On the long drain runs common here, that coating is what turns into a recurring kitchen blockage.