i want my airtime back

So i heard this rumours of people's airtime disappearing out of nowhere...Ad never thought it would happen to me cause i don't use their stupid free mode and stuff and today my airtime kept on disappearing cent by cent and well i didn't notice until tonight when i tried making a call....over R70 airtime gone and they blame it on the internet usage...HOW PATHETIC!!!! cause i bought data that expires on the 7th and i use wifi at home.....And some of their call centre agents are plain rude hanging up on loyal and valuable clients