iPhone 8 GPS problems

On both Google Maps and Apple Maps, the gps doesn't seem to keep up. The apps start up fine but once I start driving the GPS becomes erratic and loses me. Both navigation apps can't seem to locate me unless I re-start the app over and over again. I thought it was a buggy iPhone 8 so I took it back to Verizon (where I bought it) and it was swapped out for a new one, and the new one started acting the same way the moment I hit the road. I haven't used any icloud backups, I set up both phones as new iPhones each time I activated them. I also factory reset my day old iPhone twice before taking it to the store for replacement. The replacement (new) phone has the same issue. Help!