Payment wrongfully deducted and not refunded

On the 19th of July 2017 I assisted my brother and sister-in-law to book IELTS test for themselves through the website. I paid for these tests using my credit card, as they do not have credit cards. Something went wrong with the first transaction and the website sent a message indicating that the transaction was unsuccessful and we had to redo the process. We re-booked twice, once for my brother and once for my sister-in-law. I later learned that three transactions were deducted from my account and have since struggled without end to be reimbursed by the British Council, even after providing official proof of payment and bank statements.