Here is my working solution.
Just edit the functions.php
and add the following lines and replace "YOURAPIKEY"
with your Google Maps API key.
function fix_gmaps_api_key() {
if(mb_strlen(acf_get_setting("google_api_key")) <= 0){
acf_update_setting("google_api_key", "YOURAPIKEY");
}
}
add_action( 'admin_enqueue_scripts', 'fix_gmaps_api_key' );