Billing

I have home internet cable and security.  I 'changed" my internet service to business because i run my business out of my home last September and added a phone I was told I would have a 35 dollar difference.  I have called in and gone to the local office before it closed and they keep telling me someone will call me or to call a different department.  I have been paying two full bills for 9 months.  This is insane nearly 500 a month on something that should have been handled by the salesperson as he said he would.  This is not the first time I have been screwed by a Comcast sales person.