Problems with changing @mail, in dead lock with GGG unfortunately

Hi guys , maybe someone can help me with an advice

I decided to came back after 2-3 years
Downloaded the game and a unlock code pop up, what can be more easy then go to @mail and copy paste the code but here it begun

Nothing came through, unfortunately at that time i had an yahoo @mail. Ive spammed that code for 2 days, nothing came through, i tried different settings in yahoo @mail, added support@grindinggear.com to white list and other settings, nothing helpt.

So i contacted support@grindinggear.com for suport so they can change my @mail manually but for this they needed a lot of information what i provided

[Removed by Support]

In the end im in a deadlock because they cant do nothing as they have to follow the procedure.

Any ideas why @mails dosent come to @yahoo.com ??