Gift code email no redeem button
I can not find any redeem button on my email gift card. I sent it to myself from my other email adress and now I got an email for a gift code on my apple ID email but i can not manage to redeem it. There is no redeem button on it or anything else to use. Also I can not find anything under the apple ID > Gift. I did get a an invoice and the email with the gift card on it. How can I do that now or at least cancel the order if I can not seem to use it.
Thx
iPhone 6s Plus, iOS 11.2.5