DIAGNOSIS Power supply interruption. Most likely a blown thermal fuse in the motor housing from an overload.
FIX Unplug. Check the brush roll for a massive hair/jam. Clear it. Let vacuum cool 60 minutes. Plug into a different wall outlet. If still dead, thermal fuse is blown. Requires motor housing replacement.
IF THAT DIDN'T WORK Check the power cord where it enters the vacuum body. Internal wire fatigue breaks there. Needs cord replacement.
HEADS UP Never run it over wet carpet or with a full bin. Both overload motor and blow thermal fuse.