I can’t change flags

I followed the steps to create my folder:

wp-content/polylang/[flagcode].svg

But it doesn’t detect the uploaded flags…I have for example, es_ES.svg and es.svg but nothing changes, it still shows the classic ones of the plugin.

I have those files and in my code the following function (functions.php file):
add_filter( 'pll_custom_flag', 'pll_custom_flag', 10, 2 );
function pll_custom_flag( $flag, $code ) {
$flag['url'] = content_url('/')."/polylang/{$code}.svg";
$flag['width'] = 120;
$flag['height'] = 80;
return $flag;
}

I have cleared browser cache, tried different browsers…cleared site cache and nothing.

Maybe something in my configuration is wrong or missing but…I cant’ find it!

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