SPARK Schools Accounts Department is trying to SWINDLE money from me

I pay school fees upfront annually, I have been doing this for the past 3 years. Even in 2020 during the lockdown my fees were paid, when the kids only went to school for a few months. On the 31st of December 2021 I paid the annual fee for 2022, of course, it was discounted. I paid again on the 31st of December 2022 for 2023. Instead of a thank you for being a loyal client I get a response saying I owe fees for December 2022. How is that possible when I paid the annual fee and why did they even give me my child’s report card if I owe them money?

I called and I was told that this is because they did not allocate the discount in 2020, THEM, NOT ME because I paid the correct amount. Then they also say they gave my child a mask in July 2022 and I owe them R10, this R10 will affect my discount for 2023. I have never even seen a mask, my child always went to school with 3 masks, and she still has masks that were never used. I don't care much about the stupid R10, I paid for it. They still have the audacity to tell me that it would affect my discount for 2023.

I am so mad, in fact, I am ****ed off because they are clearly trying to swindle money out of me. I do not have money, I am a single parent trying to make sure that my child gets the best education. Do not try to recover the money that was not paid by other parents from the parents that pay.