MTN lies on black Friday deals for 2020

In March 2021 I raised a query on 2 contracts I hold with MTN regarding my monthly data allocation which was short of 10 gigs each. I called the call center as well as going via a store but to date have had no feedback. Took out a black Friday special for 40gigs and only receive 30gigs (special was on the 20gig package been upgraded to total of 40gig).