GSC error sometimes

That error is likely caused by an incorrect loading order of the JS scripts by WP Rocket.

The Google Maps script needs to be loaded before the wpsl-gmap.min.js script runs, which it normally does. But when you use plugins to combine scripts, or change the loading order, then this can break it.

If there’s an option to exclude the Google Maps path ( https://maps.google.com/maps/api/js ), then add that, or otherwise exclude the store locator page somewhere from WP Rocket.