I’m acc getting scammed by nucleus

So during supplementary exams this year I lost my ID card before and exam so I had to get a new one which normally costs 25 dollars but instead of paying 25, the guy freaking charged me 50 😢. The guy tried to get me a refund the same day by getting the manager but they had said they needed to “find my receipt????”. So I waited til week 1, noting, he had specified I could come back anytime and he would refund me and would leave a note to find my receipt. I come back, no refund. At this point I’ve come back at least 7 times to nucleus and I’ve spoken to 3 different managers to try to get my refund. One even saying that they cant even find my receipt and questioning if I even made the purchase, where I had to send bank statements AND my bank card number. I’m never seeing ts 25 dollars, who do u even talk to ab this ;(