What is the problem? Please be detailed.
I've heard from a couple of users (most recently @Joseph_E_Flack_IV) that they can sometimes capture geopoints that have high accuracy but impossible latitudes and longitudes. I have not been able to reproduce this myself. Users report that the same device and the same device type are successfully used in general. There seems to be no trend between locations where this happens -- rural vs urban, long time between point collection, etc. Android is set to capture points with GPS only.
What ODK tool and version are you using? And on what device and operating system version?
Any version of Collect. Devices are generally inexpensive field devices.
The discussion at Show satellites and time elapsed in geopoint dialog made me think there may be folks in the community who can explain this. Would some of the multi-point techniques described there help?