Ghosting mid research project contact
So I've been accepted as an exchange student at EPFL next semester. I wanted to do a research project, so I contacted some labs that interested me. Of course, I looked through the lab's websites and followed the instructions listed for each lab to send an email contact.
The ones that get outright no answer, I understand. However, many of the people I contacted (including both professors and PhDs) gave me an answer stating that they want to schedule an interview, then disappeared after I give them an answer.
This happened like 3~4 times, so I'm confused. Is it normal to just stop replying after responding with an interview offer? I can't think of anything I did wrong. I was always polite and responded quickly. I tried waiting or sending a short reminder after a while, but no answer ever comes.
I guess this post doesn't really have a point, but I've been very anxious these past few weaks waiting for responds that never come. I really hope I can participate in a research project, but at this point, I'll just have half a dozen of interview offers that go nowhere.