FNB connect ****med me with a promise of 500gb a month and not loaded on sim

I took n FNB connet offer for a device with sim end of Jan and now it seems I have been ****med by FNB. The offer said I woud get 500gb for the next 6months and because of this I cancelled my home wifi with Rain to give myself flexibility for the next 6month. Today 2 March FNB has not loaded the promised 500gb data on my sim-card and now have to purchase data bundles.