what did the hell Gameflip's supporter do ?

I sell CDK, but 1 guy told me 2 codes he bought is invalid. I checked then give him 2 new codes but he still open dispute.
Today i log in, Gameflip’s supporter has cancel my transactions wow. !!
Order ID:
6f8edb0c-deef-42a3-852a-693d0bd26143
f90762aa-e883-4ca2-a266-64724fbbba44

Invite code: LVBDES

Hello!

You must, in this case, open a ticket to the support team ans send them every proof you have of your codes being valid.

They will be able to help you further then.

To open a ticket, check the link below;
https://gameflip.zendesk.com/hc/en-us/requests/new

Thank you.

You canceled, all proof i has been send at histofy chat, i cant see it anymore

You don’t have any history chat logs in your emails?