Hope you got your answer. I think you know better how many accounts you have and which account has been banned previously. So according to the forum rules although forum allow you create multiple account, but if one of your account got ban then all of your accounts will be banned. Because forum banning you (the person), not only your account. Selling products on the forum wouldn't be a reason for a ban either it's legit or scam. But if you break forum rules and sell a few product which hasn't been allowed by forum then you might get a ban.