Query posts using meta_key

I am trying to rank results based on the value of a meta_key.

This is my form

<form action="<?php echo home_url('/');?>" method="get" data-javo-patch-form-for-result>
<input type="hidden" name="post_type" value="item">
<input type="hidden" name="location" value="<?php echo $javo_query->get('location');?>" data-javo-sf-location>
<input type="hidden" name="s" data-javo-sf-keyword>
<input type="hidden" name="orderby" value="title">
<input type="hidden" name="order" value="asc">
<input type="hidden" name="meta_key" value="level">
<input type="hidden" name="orderby" value="meta_value_num">
</form>

But it's not working! If you have any advice, please share.

Thank you,

Joe