Auto milk frother not working

i have a magimix m200 and bought the auto frother tube which attaches to the main frothing device. I have always regularly descaled my machine and did it only last month. Now the frother is not working. It is still heating the milk, although not as hot as before, but there is no frothing action. In fact, even when i remove the tube and try frothing with the regular attachment it is not working either. Help!!! I love my machine, which is 2 years old, but i don't always want to drink black coffee.