Hi Nanett
I have the same issue, I've written an message to the guest via airbnb regarding arrival time, no response, I've texted to the mobile number provided and have received no response until 10 pm of the supposed arrival day, I do not ofer 24 h check in so honestly I have no idea if the guest is gonna arrive (in the middle of the night???) or not or whatever....
usually most guest are nice but I guess some confuse airbnb with a hotel.....
I you can still get out of it I wouldn't host him... I have also gotten a lot more selective in accepting guests and usually listen to my gut.. unfortunately airbnb penalises hosts but not guests.....
All the best
Barbara