Bought 2 airtime vouchers but none came through.

I am very annoyed by service received by FNB connect. This morning I urgently needed to make a very important phone call, and when I last time checked I had R0.61, that was yesterday. and quickly purchased R15 FNB Connect airtime, I have this call which lasted 5 seconds, and another one 25 seconds. The second call dropped due to no airtime, how? Becuase it was important call, I quickly bought another R15 voucher, but I could not make calls, still had no airtime. So it means even the first voucher didn't come through. How does one can sooo inconvenience? I cried because those were important calls in my life, while on the road. Eventually, I managed to call FNB, and told about 48 hour investigation and for 2 times the call dropped while still hanging not yet finalised? Seriously? If i was to die, i could have died just because of FNB that has failed me.