34 gig once off not loaded

Over the weekend I renewed one of my contracts with MTN, I must say the service at the shop was good though it was slow (centurion mall) the phone renewed I didn't have a problem I received my promotion data of 34 gig within 2 hours the problem was the new sim only contract that I also took my 34 gig was not loaded I called their call center they said to me it was loaded yesterday but I'm now only left with 17gig which is not true first their prorata from 1 to 11 was just 2,6 gig out of 40gig how possible is that I believe that the 17 gig was my pro rata not my once off promotion data there's no way that I can use half of the data 34 gig in 8 hours put in mind that the other data that was loaded on my renewal I still have 30 gig and it was loaded on Saturday