Comcast is not porting my business land line to my new business cell.

I am downsizing my business.  I'm moving from a brick-and-mortar location to a home office.  I had two land lines at the old location.  I want one business cell at my new home office location, the primary line.  This business number has been linked to my business since the mid-1990s.  This is the phone number on my business cards, my website, my invoices..... This is the number that my clients know and it's the number that they call.

I first tried to activate the cell on September 4th.  I've spent many hours on multiple phone calls which left me furious and/or in tears.  Every employee has been polite, kind and professional and I believe that they want to help me. From what I understand (I don't think that I should even need to understand the process), the landline must be 'active' and without a 'disconnect order' so the line can transfer to the new cell and the cell can be activated.  They say this might take 4 to 5 days.  Apparently, there is a 'disconnect' on that account.    If the account is ever actually disconnected, I lose that land line phone number forever.  I call, I start with the business cell people, I explain everything, give account numbers and addresses, they try things, then I get moved to the land line people, I explain everything, give account numbers and addresses, they try things, then I get moved to the loyalty people, then I might get bounced back to the business cell people or the local account representative.  Everyone tries to help me, it never works. I go in circles.  I'm wasting my valuable time and the valuable time of all those employees who want to help but are not successful.

In the meantime, the billing for my cell phone started on September 2nd.  I've purchased and paid for a new cell phone which is a worthless device, unless I want to call 911.  The billing at my old location is still going on.  In fact, it's gone from $232 a month to over $300.  That is an account for a physical location where I no longer rent.  I've turned in the modem.  I can't reach into the Comcast system and push some button to remove the disconnect, push another to port the number, then once the number ports, disconnect the old account.  I'm frustrated and discouraged.  I don't want to start another phone call marathon.  How can this be resolved?