Basic Google Maps Placemarks error: bgmpData undefined.

Can someone please help translate this. I don’t know how to match my names to what needs to be changed in the code. My map page slug name is ‘availability’, my short code is [bgmp-map]:

Copy and paste that into your theme’s functions.php file or a functionality plugin, update the function names and filter arguments, and then add the slugs of any pages/posts containing the map to $shortcodePageSlugs.

I put this code into a Code Editor Plug-in:

function bgmp-map()
[
global $post;

$shortcodePageSlugs = array(
‘availability’

);

if( $post )
if( in_array( $post->post_name, $shortcodePageSlugs ) )
add_filter( ‘bgmp_map’, ‘__return_true’ );
]
add_action( ‘wp’, ‘bgmp-map’ );

My site is running on a local server, so no way to share.

https://ww.wp.xz.cn/plugins/basic-google-maps-placemarks/