Planet fitness Morningside - cheat about the fee and keep delaying

Morningside branch. The sale guy Lucky More told me I should pay only R480 for the corporate rate and free for 3 months. But everything is a lie. They charge me R599 from the 2nd month. I told the sales manager Gerald. He promised he will fix it but it has been 3 months. They just keep overcharging me, and I have the recording of my conversation with the sales guy as proof. How ridiculous are they?!