When Gannon is holding the phone across the hall. His hand drops. On the next shot, the phone is back up in the air.
Friday and Gannon arrive at the hotel lobby looking for Ralph Harmon. The clock behind the desk shows 6:55 when they first arrive. In the next lobby scene Friday narrates that it was 7:12, but the clock on the wall behind the desk shows 6:15 as the time.
When Friday, Gannon and Nina Draper are entering the elevator to go upstairs, the door is a single piece only an inch or so thick. Such a door would have to either stay in the frame for that floor, which would be hazardous for anyone inside, or ride up with the car, leaving an exposed shaft people could fall down.