HELP!!!!! How do I remove the Last Name Field in Newsletter Form?

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<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function(){
	$('.last-name input').attr('value','NA');
  $('.last-name').attr('style','display:none;');
});
</script>

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