Help consolidating accounts

I am trying to consolidate three Comcast business accounts under one email address. I currently have two accounts linked to one email address. The third account is linked to another email address.

I can't linke the third account using "Link Account" because I get an error which states that "the accout number already exists in My Account".

I have tried to add the user to the third account, but that won;t work either because email address is already in use.

There must be a way to solve this. Any help is much appreciated.

Thanks