Shortcodes showing in excerpt despite using strip_shortcodes

On my website, shortcodes are showing in the excerpts, despite the fact that WordPress should remove them automatically, and that I tried this two different solutions:

function remove_shortcode_from_excerpt($content) {
    $content = strip_shortcodes( $content );
    return $content;
}
add_filter('the_excerpt', 'remove_shortcode_from_excerpt');

And

add_filter( 'the_excerpt', 'shortcode_unautop');
add_filter( 'the_excerpt', 'do_shortcode');

That I added in the functions.php file of my child theme.

What are my next options?