How to linked all business accounts under one business account?

Hi,

I have called to customer services several times, spend hours trying to get help. My organization has 15 active accounts. I can see on MyAccount only 6, the remaining 8 are not available.

There were opened by internal business from my organizations long time ago. The invoices currently all are sent to PO BOX operated by the office which will be moved to another localization.

We do not need the paper invoice, therefore MyAccount access is very convenient, unfortunately 8 accounts will stay unsecure as my organization will lose the possibility to collect the paper invoices, we can't get the access to them neither redirect to other PO BOX. Comcast doesn't care .

Customer services requires information from registration. Employees which opened the accounts left the organization and there is no possibility to get the emails with activating link. Comcast sends the emails to an inactive email address and is not interested that no one will pick up the email. 

There are huge risks 8 invoices will not be not paying in the nearest future because Comcast is not flexible with such situation.

I'm exhausted dealing with this company. Customer Service stuck with stupid procedures and is not keen to support the customer.  They completely don't care that we have huge problem. We are medical organization we can't take the risk the circuits will be disconnected due to not paid bills, but Comcast still doesn't care. 

Is there anyone who can solve it please?????