Ladies, MRFS@yoox worked for me. However, it "mysteriously" didn't work until I contacted customer service. 

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I know! It's funny isn't it? This morning I was a bit frustrated. So I grabbed my iPad and entered the code. Then voila! it worked.
I thought they must have fixed already but I guess not?
10%off with DEFDEALS10@YOOX
They always do price adjustment if you e-mail or call with the code you couldn't use for some reason.A little OT but I wanted to share my experience.
Two weeks ago I made an order and while I was checking out and paying, YOOX sent out e - mails with 10% further sale code.
I saw it only after I paid and couldn't put the code at checkout, I was so pissed off! It was just a matter of 27 euros, but still...
So I emailed their customer service (it was Sat and couldn't call them) and explained what happened and why I couldn't put the code myself because I was already paying for my order.
The order arrived, but no reply from customer service.
A week after my order I received a notification from Paypal with the refund from yoox. I still haven't had a reply from their customer service, but I got my money back!