How can I fix my Stoves Q 900 GRF DO gas oven?

Previously had a problem with the green lights below the control knobs for both ovens continuously flashing, which is now resolved, but now got another problem. Both ovens work normally, but when finished cooking and the control knobs turned back to zero, the interior lights and fan/s keep going and can only be stopped by shutting off the electricity, however briefly, and things return back to normal again. Can anything be done to make them stop automatically, like they always have done?