Check your phone’s settings
Start by checking that the GPS is active on your phone and that you have “High Precision” turned on. If your phone’s GPS is not enabled, GLFR can not figure out exactly where you are.
Allow GLFR to use your GPS
The first time you use GLFR, you are asked if you want to give the app access to see your location. If you have rejected that or the permission for some other reason has been withdrawn, GLFR can’t display distances, etc. In your phone’s settings you can probably see which services your different apps have access to. Find GLFR in the list and check that it is allowed to use your location. Check the manufacturer’s website of your phone for information on how to do this on your specific phone.