If it was because of multi-accounts you are wrong. My cousin created his account recently and we did NOT share the same internet connection. He was using HIS laptops verizon wireless connection, while I was using MY aol dial-up connection. The only reason we now have to share the dial-up is because his laptop broke and we have to get it fixed. I was going to post a question about if I had to e-mail anyone and tell them we were going to have to share this connection for now until his laptop was fixed, but I was banned before I got to.
The Sim News announces all bans. For multi bans you can e-mail multi-accounts@swcombine.com and for other bans you can e-mail assistants@swcombine.com if you feel you have an excuse or explanation.
In this instance I'm going to be dubious seeing as you and your cousin seem to share the same name and e-mail address, in addition to the obvious lack of multi registration.