I'd try writing a formal letter to both along with a copy of your statement charge, as well as the history of your change to the regular card. I'd likely send to the corporate office of US, and main customer care of Bank of America, where they would best be able to forward to the person who is in charge of this issue.

In the letter I would include a follow up date (ie. 30 days) and follow up with another request if it is not done, mentioning BBB, etc. I wouldn't mention the CO Chase thing. Good luck!