Ive just spoken with Samsung on live chat, they sent me a link with information on this promotion
https://2021.samsungpromotions.claims/paygiveawayThe information in the link states that it doesn't matter if you press the voucher used button, you will still be entered into the prize draw. The used button is literally useless.
We just wait for a email if we win and then enter the code that they email us into the link in the winners email.
So the voucher codes and used button are both useless. We just wait to see if we win and use the code in the winners email. What a absolutely ridiculous promotion with zero information about it.
Anyway, good luck to everyone.