Hopeless MTN

So I go ****** and lost my sim with phone. Last week I went to town purchased a new phone and sim did the ussd manual sim swap, and I loaded airtime on the sim card, mind u it was a promotion sim so i received data, minutes and sms's, when the sim swap went through the next day my airtime was gone, unused. So I inbox MTN with the new number that was loaded with airtime and the voucher and I was rudely told "customers are told they shouldn't load anything on the sim while awiting" where was this stated exactly. I mean the airtime was unused, I dont care about the extra stuff I received for recharging, like seriously I just gave airtime to MTN. What a sham of a company.