Siemens induction stovetop - blinking lightand nno heat?

I am staying temporarily in an apartment that has Siemens induction stove/oven combination. The oven works fine. The hobs on the stovetop are not - when I select any temperature for instance 5, then 5 is blinking and the ring is not heating. I disconnected from electricity and this didn't solve the problem.
Model # HE 300.50 for stovetop and HE 300.80 for the oven. All my instruction manuals are in German - don't understand it. Please help.