I opened my app and found the code, but what I needed was a QR code. They said it was sent by email. Since I had made the reservation two or three weeks before, I had trouble finding any email. They very kindly took pictures of the reservation on my phone app and gave me tickets. My husband, son, and I enjoyed the whole 90-minute tour on the top of the bus on the most beautiful day with mostly blue sky. The driver was a wonderful storyteller with a calming voice. We thanked him very much on the way out, and asked him how he could talk constantly for 90 minutes and still keep his voice. He joked that when he goes home at night, he doesn't speak at all. A good laugh. Later I discovered that the email with the QR code came just the day before our tour. I've been so busy sightseeing, I haven't looked at email that much. Perhaps the driver/ticket person could know this, and tell tourists to look for an email that just came the day before.