I have had a similar experience. The only thing I can say on their behalf is, they do a lot of different imaging, so it could be that the people who are being taken ahead of you are having different tests.
I could see that as a possibility but I was not the only person with this issue even on the same visit. Another lady had been waiting as long as I had and inquired about how much longer it would be, I heard them say it wouldn't be much longer and she left. I asked the receptionist how much longer my wait would be and she went back to look for my chart, I heard them faintly say "oh" and then she told me I would be next. I genuinely feel that they misplaced my documents and that's why I had to wait. The X-ray I needed was even labeled urgent by my doctor and the actual imaging only took 3 minutes tops!
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