DATA ****** Including Airtime By mtn

my data just kept on missing from both my android contract phones and my issue is been resolved ive been calling numerous times and some I do get an operator some times I don't <br> <br> until I buy a cheap phone that is not internet compatible, only then my data will not get lost. the worst part is when they try to shift back the blame saying you've been on the internet for few minutes and R200 airtime and 250MB of data will be depleted. <br> <br> as I am writing this complaint I called the mtn customer care line , I don't mind waiting for 45 minutes to get an operator. what's ****ing me off is to GET the same explanation over again the lady told me that to read an email can consume my data, leave it half way then decides to consume airtime too. this is BULL ****!