Russell Hobbs Microwave fan and light not stopping?

Our microwave seems to be stuck on. The table turns, the light is on and the fan is on. I've unplugged it for 24 hours, plugged it back in and it started again. Tried all sorts of combinations of trying to cancel it. I can run a 30 second program where the sound changes (it starts actually microwaving). The countdown ends, it beeps, but the fan, light and turning still continues. The only way to make it stop is un-plugging it.

Thanks in advance