Replace 1305 with the filter ID

sort-numeric-options-jsf.php

<?php

add_filter( 'jet-smart-filters/filters/filter-options', function( $options, $filter_id ){

  if ( 1305 == $filter_id ) {

    uasort( $options, '__compare_jsf' );

  }

  return $options;

}, 0, 2 );



function __compare_jsf( $a, $b ) {

  $a = (int) $a;

  $b = (int) $b;

  if ( $a >= $b ) {

    $c = 1;

  } else {

    $c = -1;

  }

  return $c;

}