Second time that I have not received air time

I loaded R300 airtime onto my phone on Saturday 9 September using the direct recharge function, received an sms stating that my account has been recharged, BUT my balance remains R0.00 . I have called the customer service 6 times and NOBODY seems able to help me. Sheet Street has confirmed that the airtime was indeed loaded. This is the SECOND time I am experiencing the same problem with MRP Mobile. It is shocking to say the least. I honestly can't wait to change networks