Delayed airtime

Hi,<br> <br> I had about 14 Minutes Bonus Airtime that was Due to expire on 28 February 2015. I bought 10 Rands airtime via Telephone Banking to prevent me airtime from expiring at around 20:00 on the 27 February . the airtime did not appear, so I bought another R 10 Airtime. The airtime was only added after 00:00, and thus caused my Bonus airtime to expire. I called the call center and talked to Sanele Ngabhi, but he could not give me satisfactory response. I feel that this is unfair as I bought the airtime in advance , well before midnight to prevent my bonus airtime from expiring and it still expired because the airtime was added at 00:16 which is not my fault.