Primary User email address - how do I get it changed/updated?

Hello, 

I have Comcast Business Internet for my small company. When I started, the only email address I had was a temporary "internet" based account. I would like to update my account to reflect my business email address so that e-bills come to the right place.

I have tried Comcast Technical Support and they tell me it is not possible for them to change the email address on file. Can you help?

If it is not possible to change it, would the other solution be to close the account and open up a new one?

I hope not to have to resort to the inconvenience of shutting down and opening account, but if that's the only way to fix the problem then so be it.

Please let me know.

Thanks,

David