Jerry:
Don't know if you resolved your no GPS lock situation, but here is something that resolved my issue and the same issue if my friend. We both were using LG GPAD tablets. We would see our airplane ICON just stop moving or show us back at our home airport when we tried to reverse our flight plan before heading back to our home airport.
I got "Weak GPS" or "No Lock" messages. Pulled up a satellite app to view satellites and saw none.
Go to settings>location>mode and try selecting "Device Sensors Only GPS ONLY" for your GPS Source. The other choices are...High Accuracy (GPS and Networks) and Battery saving(Network Only)
This worked for me. Might work for you.
John M