Airtime n data disappearance

This morning i had about 58MB of data before recharging with R29 airtime and purchased a 60MB data bundle. Before i could even use it all was gone. I just called customer care and instead of helping me I'm told there are apps running in the background, mind you i had my data on before but it didn't run out that quickly. .and most of my apps run on WiFi as it's my default setting. Now the 1st guy i spoke to transferred me to internal dept which couldn't assist me as they only deal with internal matters, i was then redirected back to customer care where the lady i spoke to told me she couldn't help me. <br> <br> I am not happy with this vodacom and if could drop them now i would. Pity i'm tied to a contract (i can't wait for it to end!!!!) Now please help! And i don't want to hear about background apps because i have been recharging previously and i was able to use my data and airtime till it finished.. not having some gremlin use what i paid for.