MTN ***** FROM THEIR CLIENTS

I upgraded my contract on the day of my billing cycle ONLY because MTN cancelled my promo services WITHOUT THE COURTESY ON ADVISING ME, after my contract was not upgraded because MTN contract option were exorbitant and not competitive at all. My August 2024 is more than double. After spending 4 hours on the phone to the call centre and being cut off NUMEROUS times i am being told I have been billed pro-rata and for the new month. DOUBLE my monthly billing how is this pro-rata?? THIS IS NOT PRO-RATE ANYTHING IS DUPLICATE BILLING AND MTN IS *****ING FROM ME. Furthermore WHY if I only have a data sim WHY am I being for itemised billing?? HOW can MTN justify this *******.