350MB data suddenly never existed

I signed up for a 24-month MTN Anytime 350 contract in January last year, which included R350 airtime, 350MB data and an additional 150MB data. The data limit on my phone has been set to be limited to 500MB since then, and I've never run out of data as I have access to wifi at home and at work.<br> Suddenly today I get an sms to say that my data bundle has been depleted. The call centre agent I eventually got hold of insists that I never had the 350MB data, only the 150MB bundle. But he doesn't understand that the 350MB was part of the deal I signed up for, and which can still be seen on numerous archived websites. Why has my contract suddenly changed??? Give me back my data!!!