Delete Old Size Thumbnail

Good morning,

maybe I am doing something wrong but even if I check the box “Delete thumbnail files for old unregistered sizes” it does not cancel the old thumbnails size from the server.

In order to remove the size I did the following:
– In Setting/Media set to “0” the size
– Added also the following code to Functions.php of the theme:
function remove_default_image_sizes( $sizes) {
unset( $sizes[‘large’]); // Added to remove 1024
unset( $sizes[‘medium’]);
unset( $sizes[‘medium_large’]);
unset( $sizes[‘1536×1536’]);
unset( $sizes[‘2048×2048’]);
return $sizes;
}
add_filter(‘intermediate_image_sizes_advanced’, ‘remove_default_image_sizes’);

Do you know what I can do to remove old files of thumbnails ?

Thank you
Kind regards
Gabriele Fortunato

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