Take it you have the Android Connect System with Garmin navigation.
Check you have everything up to date by going to the Garmin 'Where to' screen (back button bottom left from map screen) then settings. Go down to map info. Latest maps are 2018.0 and (I think, not in car atm) Garmin version 3.8.
Also check software version in 'Home' then 'Android' then scroll down to version: OC.xxx is RC4, OE.xxx is RC6 and OF.xxx is RC7 (the .xxx are numbers that are car specific so don't matter for version info, just the first two letters). Depending on the version you can install Waze etc.