Hi. I think by your internet dealer, you mean isp, or internet service provider.
I have no idea what the terms of your contract with your dealer or provider are, but I think you must speak to them about it.
I have known of people recieving joke letters or e-mails from friends with such messages also. What is your isp? It would be interesting to look at their terms, but I fear they may be in German
This sounds most odd, and I've never heard of anything like it.