The card number and all the information (CVV, expiration date, etc.) are available in the app after you sign up. The plastic card is emailed to the customer using standard mail so there is risk of lose and theft.
If the customers wants to block the Revolut card while waiting for the plastic card (in order to protect from theft) they cannot do that because that might cancel the order as stated in the FAQ.
Even if it would not cancel the order it is a bad security practice to expect the users to know they should block the card after ordering the physical one.
How will you solve this serious security and money lose risk?