MTN KEEP *****ING MY AIRTIME

mtn has done it again, I just recharged my account now, within a minute my Airtime was gone, I called their help line I was assisted by Siphokazi, she said on their system they say it does appear I should switch my phone to flight mode for 5 minutes, even though it didn't make sense to me I did it anyway and I checked my balance, it was not returned back,, I WANT MY AIRTIME, they really need to stop this and calling this network BOZZA NETWOR****!