10 years gone now, still NO Diploma

I was a student at ICESA in 2010. The fees were high. However, I made every effort to ensure I completed payment. In the year 2011, I went back to campus for 2 weeks, foreseeing that I would not be able to afford fees I dropped out. In 2012, I returned to complete my studies as I had saved up enough during the break I took. ICESA accepted me in 2012 and did not inform me that there was any outstanding balance from 2011. However, after completing the year and paying my fees for that year I was told I owe fees for the year 2011. The whole amount as though I studied with them for 3 years. You can only imagine my shock and dismay! I never received my diploma from ICESA even though I paid for and completed the 2 year course. In the year 2021, I contacted ICESA accounts department (this wasted 2 years of my life and the little money I had, it's not easy to move on) I was told I owe R18000 in order to get my diploma. When I queried further the accounts department stopped responding to me. I asked to speak to a manager and received no response. I paid this institution over R30 000 of my hard earned money and I studied hard to pass that course yet I'm left with no answers and no diploma. I am desperately looking to confront this issue face to face with the management of that institution. I need an investigation to be conducted, why accept a student back after a gap year and allow him to continue paying and not inform him that there is a balance for a year not attended?

Did anyone else experience a similar situation with ICESA? Is there anyone that can assist me with this issue? PLEASE HELP