Payments issues and cancellation

I don't even know where to begin, from being sent sent 2 payment links the first month, and was told it was an error, then sent an incorrect amount again last month when I asked for payment link sent me R915 instead of R1350, support department does not assist at all make life even more difficult, I will be cancelling these services, Rentoza has really disappointed me, and when asking to change pay date and bank details why do you have to pay 300? And why is is iphone 11 still R1350 when it's being advertised for R950 now since there is now an iphone 14