why!?

I upgrade my internet DSL connection to cable. 

Activation occurred on 04.Oct. 

Now I have no DSL or Cable connection. I also called customer support, many times, I reset modem, I gave my mac address from modem and still is not working. 

They did a "reset", still not working.   I use Cable connection, the router is Fritzbox 6660, in a 3 (drei dose). One is for TV-antena dose, is working, one for "cable" no working and radio

I have also tickets opens, but even if I check the ticket status still the same, on review..worst!!

I'm surviving with mobile internet. 

Any idea how to fix this? 

Thanks everyone!!