I also have a five-year guarantee on my machine according to the promo, but I was content to take a screenshot. I don't think De'Longhi sends out confirmations.

I asked for the certificate again by email, then had to send the proof of purchase (invoice) and a screenshot of the registration, a few days later I received the certificate. It's a pity that you have to ask for it, actually it should be sent automatically after registration. But it worked out promptly.

I received the confirmation by email on the same day I registered on the homepage. The registration should also be visible under the personal account.