What if the seller sends the wrong PIN?

The first time I bought a PIN code from the seller, no problem, the second time I bought two, one can be used, one can not be used. How should I defend my rights?

Hello,

You can open a dispute (do not complete transaction) and send proof that it didn’t work.

You should also contact Support as well regarding that.
https://gameflip.zendesk.com/hc/en-us/requests/new

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