Shocking service for a loyal client

3 months in a row now I have not received my correct allocation of data as stated in my contract. 3 visits to the blue Route Branch. Numerous emails which mostly are not rep**** to. Numerous messenger chats which are a total waste of time and still nothing. I am of course being charged for the data every month. Signed for 3 gigs and get one. This has been ongoing since the 12th June. The service is diabolical. I have been an MTN customer for over 20 years and have never missed a payment. Appalling Appalling Appalling. "What now?" one asks!!!!!!!