BOSCH Let Down

I purhased a BOSCH Athlet, 25.2 V Lithium Power Cordless Vacuum some time ago and to say I was pleased with its performance is an understatement. But I am no longer able to use it as the small wheels on the Brush section have worn right down. I mailed, in English, the only BOSCH address I could *** asking to buy a new set of wheels. They rep**** in German. Again I mailed requesting a response in English...to date I am still waiting.