If that is the advice and explanation your IP provider gave you (without recommendations on fixing it) then you need to change providers.

Someone from inside your house, or if you are using a router, someone within range of that router hacked into your network and posted that message.

It's important to protect your network because there have been people who will park outside your house and use your unsecured network to do illegal things with it - like drug transactions, bank fraud and child p*rn. In your case, someone must have parked outside your house and instead of doing something illegal, decided to reply to your chip auction just to embarrass you. Lucky for them someone caught it or their plan wouldn't have worked.

Whoever wanted to embarrass you really jumped through hoops to do it.

I hope you figure it out.