Unfair treatment

I ordered a write on the 9/3/2022 with ref ***and device and simcard were delivered on the 16/3/2022 and the number for the sim is ***and my supcription was R269 which my debit date was the last day of the month. Then following year 2023 May my debit increased to R278,90which i paid until i received a message saying on 30/9/2023 R569.44 will go off on 30/9/2023 with Ref no ***and it said your order has been submitted of which i don't know what order was submitted. I then defaulted or missed a payment and amessage was sent to me reading as thus 3/10/2023final reminder of R580,94 i then made a payment at an MTN store in Sandton of R860 on the 27/10/2023,then November i got a message saying my contract will increase from R181,71 to R 563,47on a month to month basis on 2/26/2024 as it was a 2 years contract and then 21/12/2023 an amount of R353,85 was deducted. And knowing that most people gets paid early i was surprised when the debit went off on this date 21/12/2023. 1/21/2024 again R353,95 was to be deducted in my account of which there were no funds and my debit date was changed and i don't know by who,then 2/27/2024 R282,8 was deducted plus the R353,95 which and reconnection fee which summed to R1 125,50 and when i called to ask who changed my debit date from the billing department i spoken to Thabile who said she is unable to assist me with finding who changed my debit date as her system was offline,called again and spoke to Simphiwe who too said he doesn't have the full records on the system,i then called again and spoke to Vuyelwa and i had been not given a straight answer as to who changed my debit date and to date i will can't pay MTN as i feel whoever fiddled with my account messed with my finances i mean who has money on the the 21st in their account? So now i owe MTN because of an agent who felt they should change my things without me knowing. Please assist me on how to deal with this and I'm now in debt cause of this router and sim. my email address is *** I would appreciate their response as my contract was ending March but now i find myself in this predicament.