I assume you're using Trimble Access. When you observe 2 or more points, after storing the second point you'll get a list of points observed and their residuals. You can tap on the point and there will be a "details" or something like that. It'll take you to options where you can use/not use the point or make the point be used for 2D only, or vertical only or 3D. And if you use TBC, there's ways to remove points from resections in there too after field work is finished too.