You'll need to fit a new element.
Hopefully this will be the only problem with the appliance.
If you go to www.bosch-eshop.com
Select your country.
Click on the parts icon on the right of the screen.
Put the E-Nr number from the appliance into the search box.
Click on the parts link in the centre of the screen.
This will get you the exploded view of the appliance.
Find the page with the element.
Press and hold the left mouse button, drag the box over the number adjacent to the heater and then release the mouse button.
This should open a page with the part and the price.
Click on add to basket and continue to purchase.
Alternatively, note the part number and search online to see if you can get a better deal.
Good luck with it.