We arrived to the airport. Collecting the baggage. Then started to find out what is the next. Opened the Viator App and texted the operator via the App. No answers. I went around the airport and asked people about Viator. No one has even heard about it. Finally outside of the building one bus driver of an other operator realized - based on the photo of the buses that our Viator reservation printout contained - that it might be VIP travel or so. He sent us back into the building and suggested looking for a young man. Finally we found him sitting on the counter of the Information service desk :-). Asked about VIP travel and he started to smile looked up his papers and told that he would order a car for us. We were very happy. Than the bus arrived we sat in it. After this the bus went around the terminal collecting a lot of people, delivered them in the city, finally delivered our as well. I took more than 1 hour. (An Uber could take 20-25 minutes.)
Actually we are at our hotel, which is fine. The bad thing is that no one had any idea how the second leg (our travel back to the hotel) will be organized. I believe I have to call VIP travel and ask for their help in spite of the fact that I communicated everything (departure date, flight number etc.) when I made may reservation at Viator. I hope that they have a call center or so and will be able to arrange our lift backward to the airport.
It is important to note that this was not the first time we used Viator as service provider (including Hawaii and Seychelles) and we were satisfied so far.