Map not showing after doing a walk

Try this;

To see the map, you must turn on route tracking. On your iPhone, go to Settings > Privacy > Location Services, tap Apple Watch Workout, then tap While Using the App.

Then tap on maps then tap While using the app.

Another place to check is on the watch in settings/privacy/Location Services and make sure this is turned on and scroll down to apple watch workout and select while using the app.

Your welcome.