I just want my cash back!

Last year December I paid R 2 600 to enroll in Code 10 driving lessons + a truck hire on my test day. I ended up doing one lesson because the driving school had truck problems ( which was never communicated to me). Every time I contacted the instructor (Kelvin) he told me to contact the office. I expressed my disappointment to the manager and we agreed that I can cancel the lessons and I won't be charged the service fee and cancellation fee since the problem came on their side. They claim they offered me an alternative of converting to Code 8 and a package upgrade hence they had to charge me the cancellation and service and paid me R 1 135. I have a paper trail of emails and texts proving that I honored my side of the contact (that I presented to the manager Imtiyaaz Riley) and he agreed to pay me my outstanding balance but hasn't since. It was poor communication from the beginning. I paid for a specific service and it was not delivered. I have tried to be understanding but it appears we have reached an impasse and as such resorted to this. I just want my cash back!