iPhone 6 GPS only ‘sort of ‘ works

Since 12.1 update, gps works at the start of the trip then freezes for periods occasionally working briefly but basically lags way behind so is pretty useless. I deleted maps, google map and waze. Tried mapquest which was accurate exactly as car was moving for a mile or two. Then it froze in place pointing the wrong direction etc. at end of commute 20 minutes later it resumed working for my last two turns onto my street. I tried all the resets and toggles reiterates in many useless articles.

[Edited by Host]