I booked the Antelope Lower Canyon Tour through Tripadvisor on October 1st, 2021. I believe that I have selected October 3rd, 2021 as the date for the tour. Together with my family I drove down to the Ken's Tour site for 5 hours. And when I got there it turned out that the booking was actually for the next day - October 4th, 2021. The Ken's Tour manager Zack Welch offered me the full refund, because the reservation was made less than 72 hour ago. However, when he saw that I had booked through the third party, he said to talk to them. Tripadvisor forwarded the case to Viator and they said that they need the written consent by email from their supplier for the full refund. The Ken's Tour manager said that they will be looking for the email and will reply immediately. It turned out that they never received the email, because Tripadvisor's or Viator's supplier was not the Ken's Tour, but some other aggregator by the name Wannar Travel.So, in summary, Tripadvisor accepts payment online for the service they do not provide, Viator receives payment for the service they don't provide, Wannar Travel impose the policies for the service they don't provide and the tour operator that actually provides the service can't follow their own customer service agreements because booking has been done through a third party.The word of advise - you can use Tripadvisor for search, however, never pay through Tripadvisor but rather go directly to the actual service provider site and buy there. It will be cheaper and you'll receive better customer service.