MTN - Paid for airtime I did not receive!!!!

I purchased airtime using the MTN app, the money went through my bank account however I did not receive my airtime. This was on Sunday - 7 Feb, yet I have still not received my airtime. Have spoke to literally 10 people at MTN, have sent through my bank statement. They told me 2 to 24 hours this was on Saturday - 13 Feb....still no airtime.