Not responding to closure request

I have been requesting closure of the account 3 times. No one is responding in writing that the account is closed. I recently discovered that my jet account is also a RCS account. I did not apply for it and had the Jet account over 20 years. The change came when the company was bought over. I DO NOT want the account or any Jet account for that matter. Account was settled in full last month and I need confirmation that it is closed