When I used a matrix sim card and got overbilled against usage, I thought my monies will never be refunded. I still tried, called their support them all geared to argue my case. I was rather taken aback when they heard everything politely, and apologized for their mistake and asked where would I like the refund, card or bank! I did get a refund within 7 days and this tells something good about the company. Not every bad experience ends badly. I would definitely want to use matrix sims again in the future, only because I was treated properly.