Fnb connect sim card *****

I opened a connect fnb simcard in and was promised 15 gig for 3 months and to my suprise l was given only 500mb when l called the 1st time was promised it will be done in 5 days and after 5 days still nothing ,l went to the bank and we called the connect call center and was informed that it won't be done...l m so disappointed with false advertising misleading the customer which is a violation of my rights as a customer