School Of Open Learning — Money Deducted but not rfunded after 1 Months 10 days

I had made payment for the 5th-semester admission but while doing the payment it got an error and the payment was deducted from my bank account. I waited 24 hours and then made payment again because the last payment was not reflected so I made payment again. Now It's been 1 Month and 10 days but still have not received any refund from du sol.
I request you to please refund my amount back. I have also sent some mail to sol but got nothing.