my macbook location can't be determined.
A few days ago I noticed that Location Services stopped working on my Macbook Pro. I go to the Maps app, Google maps in Safari, time zone in settings, etc. and all either report that location cannot be determined, or (in the case Google Maps) report my location is 20 miles west of where I am. I have two Macbook Pros on High Sierra: same issue. My wife's Mackbook Pro on Sierra has the same problem. All the location-related settings in Privacy and Date & Time are correct. Find My iPhone in iCloud sees my Macbook Pro, but says: Online, no location available. Siri says the same. Until a few days ago, this always worked perfectly: Maps, Google Map, and Find My iPhone could locate me perfectly. (All three register my location precisely on my iPhone and iPad, but not on computer here.) The service provider hasn't changed. What gives, and how to fix? Thanks....
MacBook Pro, OS X Mavericks (10.9)