I forgot to mention that I changed to the developer channel. I'm not sure which of these changes was the most effective.

Good news, I finally make it work. This old trade from a nexus 5 did the trick.

1- Before restarting, turn on Wi-Fi and Location detection
2- Restart
3- Run sudo restart ubuntu-location-service from the terminal
4- Open the SensorsStatus app and navigate to the GPS screen
5- Wait until the GPS starts working

https://forums.ubports.com/topic/1802/nexus-5-gps-errors-and-other-issues/42

@stanwood Lucky you, I see that someone just posted the same problem in the pixel forum "GPS interface not found". Curious to see if it will be resolved.

@stanwood Thanks a lot, unfortunately, I did reinstall, with the image of the installer (vendor.img lavender). Do you have the global version ?

Hello,
I installed Ubuntu Touch on my redmi note 7. Everything works fine except the gps. When I run the test_gps command, the response is 'Ggps interface not found'. Location is ON. I waited hours inside outside, reboot several time, reinstalled everything.
Then I thought that maybe the internal gps was broken. I reinstalled lineagesos with gapps. And I managed to get a Fix.
After reinstalling UT, again, nothing.

I am open to any suggestions.
Thank's for your help