MTN CALL PER SECOND DISCONTINUED

I've been with mtn for the past 20 years, and used their call per second price plan in its various forms over the years with great efficiency, keeping my monthly usage to the minimum, as i don't spend time talking. Since about middle of this year, 2023, i've been automatically moved over to one of their other price plans. THE RESULT BEING USING 3X>5X MY USUAL AIRTIME i've tried *136*4*2# ...to no avail tried *136*4#...no call per second price plan...i tried customer care, they just tell me they are working on it THIS IS UN-ACCEPTABLE I'm very un-happy with this outcome, and feel that if that's the case, i'm moving to another cell provider.