Android Auto not connecting on Galaxy phone
Android Auto not connecting on Galaxy phone
Restart your phone.
Swipe down from the top right corner of the screen to open the Quick panel, and then tap the Power icon. Tap Restart, and then tap Restart again to confirm.

Clear the cache for Android Auto.
Swipe down from the top right corner of the screen to open the Quick panel, and then tap the Settings icon (the gear). Tap Apps, and then tap Android Auto. Tap Storage, and then tap Clear cache.

Check for software updates.

Check the Bluetooth audio settings.
Open Settings, then tap Connections, and then tap Bluetooth. Tap the Settings icon next to the paired car, and then make sure the switches for "Calls" and "Audio" are turned on. If additional options like Contact access or Message access are available, turn them on as desired.

If you're unable to turn on the switch, tap Unpair at the bottom of the menu, and then tap Unpair again to confirm. Swipe to the very bottom of the Bluetooth menu, and then select your car from the Available devices list to re-pair.
Contact Samsung Support