We're in Istanbul and wanted to to see the Hagia Sophia. I should have checked (!) but the first website that appeared was GetYourGuide and I thought it seemed legit. I bought 'tickets' for the 'Hagia Sophia Experience and Museum'. It turns out, that wasn't the Hagia Sophia, but a separate building which in large part was an interactive experience with screens and an audio guide - we discovered this later.We arrived 10 minutes later than suggested, but 5 minutes before the tour was due to start. The guide wasn't there and when we asked at the ticket office they said that we hadn't bought tickets for the museum - we had tickets with GetYourGuide - and as the guide wasn't there there was no way of getting in.We ended up having to buy tickets again.