You may also find it is because you are in Perspective mode and the point you are locating is actually a long way away.
You should find if you click on an actual node of an existing element it will work.
You can also try turning on the surface snap as that will let you snap anywhere on a surface.
Barry.
One of the forum moderators.
Versions 6.5 to 25
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
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