add_filter('frm_fields_in_form', 'frm_remove_likert_in_form', 10, 2);
function frm_remove_likert_in_form( $fields, $args ) {
	if ( 13 == $args['form']->id ) { //Replace 13 with the ID of your field
		foreach ( $fields as $index => $field ) {
			if ( 'likert' == $field['type'] ) {
				unset( $fields[ $index ] );
			}
		}
	}

	return $fields;
}