AT&T review: Office at hand

I received a notice in December about a past due balance on my account. I sat on hold and got transfered from department to department with no answers at to what this past due balance of $749.97 was for. I learned today (12/16/24) that my toll free phone number through AT&T Office At Hand had been migrated to a different account per an FCC request dut to taxes, surcharges and fees being billed incorrect. I was paying $55.00 a month on auto pay since before 2007 and now I am told my monthly charges are $116.44. I did not receive the migration notice, a monthly bill or the email about the migration as I have called AT&T many times to update my email address but nobody seems to be competent at AT&T to do their job. The mail went to my old email address that I have called numerous times to change. If I had receied a bill for $116.44 I would have cancelled the first month...now I have a bill of $1,003.07! I cannot afford to pay this month each month for a seasonal business phone number. I am being unjustly charged by AT&T and I need this to stop. I want these charges removed and my 877 number released so I can find a business who has fair business practices handle my number as AT&T does not. My phone number is [protected] and my email is [protected]@gmail.com. I hope to get some help on this issue.