i added setting same problem
function mb_allow_subscriber_uploads() {
if ( is_admin() ) {
return;
}
// Replace 'subscriber' with the required role to update, can also be contributor.
$subscriber = get_role( 'subscriber' );
$subscriber->add_cap( 'upload_files' );
}
add_action( 'init', 'mb_allow_subscriber_uploads' );