Mint Mobile complaint: Refund Request

Mint Mobile:
I am filing a grievance based on your decision not to issue me a refund. I would like this matter reviewed by a top level supervisor, please.
I understand the refund policy. However, I believe my situation still warrants a refund.
I had been trying to work with my former carrier Straight Talk in getting my phone unlocked. They were uncooperative, and I could never get my phone to unlock. If you look at my account history in recent weeks, you will see I worked with two representatives of Mint Mobile concerning this matter. With the first one, in early September, I nearly requested a refund, but then I said I wanted to work with Straight Talk a few more days to see if I could get the phone unlocked. Then on September 14, according to my records, once again I failed completely to get my phone unlocked. I asked the representative to issue me a refund. He said that I was entitled to a full refund because I was never able to use any of your service. He did not say anything that I would not be entitled to a refund because I was outside of the 7 day period. I asked if I was entitled to an entire refund of the $53.07 I initially paid, and he said yes. He said he would process the refund and a ation would be sent to my email. Weeks went by and I never received the ation, so on Sept. 27 I re-called Mint Mobile about my refund. The representative said my refund was in process, and nothing more.
Now, today, Sept. 29 I receive this email from you saying my refund request was denied.
I am not happy with this decision, because I was told by your representatives that a refund would be issued because of my unlocking problem which could not be resolved, and nothing was stated about the 7 day refund period. I believe an exception should be made in my situation, due to the reasons I have stated.
I request a further review of my case by a top level supervisor.
Thank you,
John Kromka