Maps API key not updating

Hi,

The google maps api key isn't updating when added to the metabox.

after a long time trying to debug google maps, the error is coming from the metabox plugin,
The key shown when inspecting the page shows the fallback key.

// Default API key, required by Google Maps since June 2016.
// Users should overwrite this key with their own key.
'api_key'      => 'AIzaSyC1mUh87SGFyf133tpZQJa-s96p0tgnraQ',

I've edited the plugin so show my own api key, but is this something you'll be able to look at please?

Thanks.