Poor administration assistant and refund process

I've had to cancel my studies due to an error made by the institution at the time of registration and I've followed the necessary steps according to the rules of the institution. When I was advised regarding this, there were prompt responses I now need to receive my student deposit back and I'm being made to run from pillar to post in order to receive my refund. I was told on the 5th of April thar my POP, which I used during registration and that was processed with no problem at the time, is ******* and they cannot access it. I sent these documents again on the same day. I made follow ups following week and I got no response confirming if these were received. It is now later into another week, the 18th of April and I got told again that the same issue is the same document that I sent countless times.

The funds reflect in my student account already and these are funds which were reversed when I made the cancelation, that I need to receive back as the account states.

But no one seems to see the refund process through because of the said missing documents which I keep sending and receiving no reply.