The golden rule: When you buy gift cards, buy them from trusted sources.
It is suspicious and you have a lot of alternative options (Coinbee,BitRefill,...etc,)
[1] so there is no reason to use them.
Since they are since 2016 and there are not many positive reviews for them, this is a bad sign.
They do not offer a lot of cards and most of them have a balance greater than $ 50, so there is no need for adventure.
They may sell stolen or hacked cards, so your account may be frozen, or you may face legal problems.
[1]
https://bitcointalk.org/index.php?topic=5208530.0