This usually means the thermal fuse has tripped because the unit overheated. First, unplug it and let it cool down completely, at least 30 minutes. While it's cooling, check that the carafe is correctly seated on the warming plate. If it's off-center, the heater stays on with no load and overheats.
- After it's cool, plug it back in.
- Make sure the carafe is centered on the warming plate.
- Try starting a new brew cycle.
If it trips again immediately, the thermal fuse is likely blown permanently. There's no user reset for that. The unit would need professional repair.