What is the ruling on selling phone cards for a profit?

Question : He says: Phone cards are sold by the ministry for a certain amount, then one of the shop owners buys them and sells them for a profit. We have heard people say that this is forbidden because this card is not a commodity, but rather a substitute for its value, money for money. What is your opinion in this matter? If you wish, we can show you this card.

Answer : No, I am not afraid; I have seen it, and there is nothing wrong with a person taking it for a profit, on the condition that the ministry is excused for this, because these people brought it from the ministry and worked on it, so they take for the effort, for example, five riyals.