he chrono is supposed to be within 15 inches of the gun. When the unit is on the bench and I'm standing in a shooting position, it is about 24 inches away. Add that issue to the short distances and I'm guessing that's the problem.
I picked up an inexpensive table-top tripod on Amazon. Sitting on the bench it puts the Garmin high enough to be within 15” of my handguns when I’m standing. It also makes it easier to see the display from my shooting position.