Terrible Customer Service Retention's Department!!!!

I have had 2 contracts with cellc that has now come to an end , i called in early December 2019 to give a notice so i dont go into a month to month as i am moving abroad. The agent i spoke to advised that my numbers will be moved to prepaid on 05-01-2020. I asked the agent what will my last bill be and i was advised that it will be a pro-rated charge from 01-01-2020 to 05-01-2020 agent could not give me an amount. I was happy with the information and terminated the call. I then called in a few days ago and spoke to another consultant to get the amount that i will need to pay as advised by the agent that was to be pro-rated , this agent advised that this is not the case and that i will need to pay the full amount. I advised agent that i was advised differently and the agents proceeded to listen to the call and then she agreed that the agent did say i will pay a pro-rated charge , agent then advised this recording will be fowarded to the billing department and a manager and someone will get back to me , no1 did. i called in to the retentions dpt today and spoke to the most unhelpul frustrating agent in South Africa! the agent refused refused to confirm his name when i asked and refused to let me speak to a manager. I then told the agent that he is going against ICASA rules and he asked me what is ICASA?? The agent then told me he is terminating the call and i told him i am not giving you permission to terminate this call and i dare you to hang up i will take this to the ombudsman and you will lose your job , he then muted the call !!!! How are you employing agents in your retention's department ?? i never missed a payment and my account was always up to date now that i am querying the final bill which was incorrectly advised by your consultant i get treated like this ?? I really hope this post goes to the eyes of someone that is willing to hold up the name of CELL C as i will be taking this higher. Please can someone listen to call recordings from December 2019 to date and assist me