Bad service

Last December a call centre agent contacted me to notify me that they are changing my contract plan to something with less minutes and more data at a lower installment. I agreed to this and specifically asked if it will be lower than my current installment. The agent said yes and provided me with the amount. I am now being charged R120 more on my account than what I started off with. I called the call centre and they just keep putting me on hold and passing me around. I would like my call recordings. Very poor service