AeroPoints need a clear view of the sky above 15 degrees for us to guarantee good results. If this isn't the problem, the failures that you see are most likely due to placing AeroPoints near obstructions such as trees or buildings, or accidentally moving the AeroPoints.
If you are certain that this has not happened, we can attribute the error to other sources such as atmospheric conditions (effect of ionosphere and tropospheric refraction, which may cause the distance to deviate from its true value); satellite geometry at the time of the AeroPoint survey (position dilution of precision); and other external factors which are out of our control.
I still can't do it!
We wrote these articles to arm you with everything you need to get the job done on your own, but we understand that sometimes this isn't sufficient.
If you're stuck, the Propeller data success team may be able to help. You can contact our support team by clicking the support tab on the top-right pane of your user portal.