G2A Refund method:
1) Open the case on G2A
2) In the case claim that the license key is not working and you want a full refund.
3) Done.
Enjoy! free $150 method.
This is an automated method that doesn’t require social engineering or lying about working codes. LOL Well, there is obviously some sort of "lying" (and stealing) involved while it might not be person to person.