Your phone has a cross Firmware. For sure a Sprint version (G710PM) with a 710ULM firmware flashed. LG bridge DO NOT GOING TO check your phone.
If you want to update to latest pie firmware you can do what I (and others) did, to flash manually the firmware by youself. I did it twice, my wife's phone and my own phone. 5 minute and you gonna have Pie 9.0 with 1 Oct. 2019 security patch.
Link with instructions
<<Here>>
Good luck!