Import meta key post_count_views into your count views

Hello team !
Swiching from theme to new theme. New theme successfully uses your plugin which looks very functional and reliable.
new theme output views meta in post.

Right now my theme (old) store views in custom field with meta key post_views_count

Tried to import the views via snippet

function custom_pvc_import_meta_key( $meta_key ) {
// Use your meta-key here
$meta_key = 'post_views_count';
return $meta_key;
}
add_filter( 'pvc_import_meta_key', 'custom_pvc_import_meta_key' );

but it does NOT import anything. Post counter remains at 0.
Note : no cache used.

Do I miss something next the snioppet ?
The import button as you suggest just import from P-PostViews plugin.
Looked into the forum but nothing that changes this.

Any tip or correction is welcome,
Thank you !