Hackers Intercepting MTN Recharge Card Credit?

I just loaded a recharge card successfully, but when I tried to check my account balance, I could not find the credit there.

I contacted MTN customer care unit immediately, I was asked to provide the card serial number which I did.

After some verification, the guy asked me if I received any call from the number 333 or text message of any sort from the same number, I said no, cos, I never did.

It was then that the guy told me that I wasn't the only person experiencing it. That some guy hacked into their system and he's hijacking people's credit while they tried to load.

Has anybody experienced the same thing recently?