BAD customer experience

Ive just received the most appalling pathetic customer centre from Cell c. Ive been a customer for many years I have also promoted my household to your network BUT after the level of service I have received now Im DEFINITELY changing my provider. My experience within the last 2 months has just been a nightmare. I currently have 2 data contacts with Cell, 199 amd the other 99 both 20gigs. Last month my wife received a called from the sales which they promoted a data sim 'LTE A' for R149 a month 15 gig anytime, I then called back requested to change both, however I was told that I can only change the 1 because my 2nd contract expires 27 May confirmed by your retention amd in store, however I can provided I pay a penalty. I then decided that I rather wait for the 2nd contract to expire then change. The contact that I changed only lasted for a day or 2 because I was not advised that I cannot receive or make calls I then change it back to the previous contract. I viewed my balance and was shocked at my debit amount. I then called spoke to Amanda whom was utterly rude and has no customer centric s****s placing me on mute and hold while Im speaking. The agent serves no willingness to help as she places me on hold after every question asked to get information "not sure if she knows ur product'. She speaks constantly over me raising her voice getting irritated with myself 'A CUSTOMER' and not trying to help. All I wanted to know why am I in a 26 month contract and why have I not been notified of my billing amount being changed and I have no knowledge of your invoice amd requested the Amanda to give me a breakdown. NB TEACH YOUR AGENTS YOUR PRODUCT BEFORE PLACING THEM ON THE PHONE AND MOST IMPORTANT TEACH THEM HOW TO DEAL WITH CUSTOMERS CENTRIC. I hope my complaint does not fall on deaf ears.