After completing the order, I found that the voucher stated that a physical copy of the voucher must be printed for redemption. However, upon arrival, you can show your phone to the ticket counter staff, who will write down the number on it, and then you can redeem your ticket. When redeeming tickets, you still need to queue with those purchasing tickets. Although it was cherry blossom season, we entered two hours before closing, so there were significantly fewer people and no waiting. It's truly worth going up to see during cherry blossom season; it's incredibly beautiful.