If you lose the credit card with which you made the purchase and supposing that you have not already printed the ticket or saved the PDF file, in order to print a ticket at the club ticket offices you will have to provide:

• A bank document certifying that you were the owner of the card that was used to purchase the tickets.
• Document (DNI, Passport) certifying your identity and/or status.
• Proof of purchase (email to confirm purchase, receipt, etc.)