A hum without normal progress is a symptom to report, not an instruction to help the drum by hand. Several conditions can produce similar sounds.
Understanding this situation
Do not repeatedly press start or reach inside while the appliance is powered. The selected programme, door status and display are useful details, but they do not identify a single part remotely.
A useful next step
Leave the dryer unused if it remains abnormal. Record what happened at the first attempt and any accompanying heat or smell. Arrange assessment rather than bypassing the door switch or pushing the drum into motion.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.