Comcast billing issue using autopay with business checking account

Just started a Comcast Business account for internet. Got the discount for using auto-pay. Provided the correct routing number and banking account information.

they went to withdraw the first payment from our bank, our bank never saw the transaction. The payment was returned, Comcast now states that only debit card or credit card can be used to make the payment. They have blocked the use of a business checking account. I called customer service 8 times, they cannot do anything, they state our bank blocked the payment. that is not true, our bank never saw it try to come out of our account. Customer Service states that the last four numbers of the bank account are correct, but the emails we get from Comcast state that the last four numbers of our bank account are not the same, it actually shows the last four numbers of our bank account to match the same last four numbers of our Comcast account number. Somethingis incorrect on their side. They tell me to remove the block, it will take 6 months for their error. I need this resolved ASAP, next they will suspend service based on non-payment. I would love to pay, but refuse to be bullied into using credit card or a debit card for a business account that was initially set up to ACH from our business banking account. Agents cannot escalate as they cannot do anymore.. Also the web developer on this forum needs to learn to make the page fit the screen. I had to reduce to 50% just to see the post button and the lower portion of the form. Yikes ....