Gustazos - paying online

I've seen a couple of good offers recently on Gustazos. But....Had problems with payment. My Bancamarch card attemot asked for what in the UK would be Verify by Visa.
I tried to sort this by filling in a form online but was eventually told that it wasn't available for me.
I then tried to pay with both of my UK credit cards as well as a UK debit card. All three of these were rejected.
Any solutions out there? I am sure I have bought Gustazos before. Most annoying.
I would add that we aren't talking mega bucks here - probably about 25 euros.

We use them lots, via a Santander card, never been a problem, best check with card issuer as never been asked for code with small purchases like these, good luck

Thanks for the reply. It remains a mystery to me. I actually asked in Bancamarch and they were very unhelpful.
For anyone who hasn't heard of Gustazos, it is similar to Groupon. So annoying. I can't buy one at all it seems as credit/debit card seems to be the only option.

Ah, we use a Santander Mastercard, debit and credit i tink, though its always been used as debit, maybe Gustazos has had an issue with your bank's cards.