How can I open a new account with Charter after an old one was sent to collections?

I have an old account with Charter that went to collections about a year and a half ago due to an outstanding balance and equipment I failed to return. Today I called to open a new account and was approved. Will they add the balance from my old account to my new one? How can I be approved if the old account (which was also under my SSN) was sent to collections? I fully intend to pay the old account but am suspicious about the new account. Any advice would be appreciated. Thanks.