It is Nougat I guess. Such problems occur in it.
Set permissions and behavior in Android system app settings.
And that have nothing to do with neither with the Pongo nor with Nextgen.
Such questions are asked in [Only registered and activated users can see links. ], although they do not belong there either.
Edit:
messing up with schemes, can cause some other problems
Edit2:
accuracy_workaround=0
fix problems with satellite detection which cause crashing NG.
Then, you have problem with device, not a stable signal reception.
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