At&t won't let me cancel Internet

I've cancelled my business Internet twice now and it still shows as an active account on the at&t app. I was told on the first call to cancel that I would receive an email on where to return my equipment but have received no such email. After that call to cancel, my account that was in good standing suddenly changed to "suspended", yet still no information anywhere that I was the one to cancel it. Since the first attempt of cancelling, another billing cycle has been added and an unauthorized autopay was deducted from my account. I once again called to dispute the new charges for an account that was to be cancelled back in Dec. Of course I got nowhere in explaining this to the representative and he basically just repeated back to me what I said to him. However, he did state that he would make sure my account would be marked as cancelled. 

That was last week and here we are again, no email and no proof anywhere that I have cancelled this account. This is absolutely crazy. Noone should have to spend so much time making repeated phone calls for the same issue. If this is how they treat "business" accounts, I'd hate to see how non-business accounts are handled.