********** mtn data

The call center Consultants have not been able to help me. I'm exhausted I have 500MB data inclusive of all social, internet and sms bundles. But every time I open Facebook, Twitter etc, it's says my airtime may be too low. So no videos and no images open on my fb account. Even if I buy 2gigs of data, it refuses to open/download. MTN PLEASE I NEED ANSWERS TO THIS, I'M TIRED