Display taxonomy name in entry

<?php
/*
1. Edit your form in WP admin. Delete all values in you custom taxonomy input field.  Uncheck "enable values".
2. Goto "Advanced" tab and uncheck "Populate with taxonomy".  This will make values the same as label name.
3. Add the code below to your functions.php file.
*/
add_action('gform_after_submission_YOURFORMID', 'gform_chnage_id_to_name', 10, 2);
function gform_chnage_id_to_name($entry, $form) {

    $taxonomy = "YOURCUSTOMTAXONOMY";

    foreach( $form['fields'] as &$field ) {

        // In my case I use checkbox, but maybe it's different in you case.
        if ( array_key_exists( 'type', $field ) && $field['type'] == 'checkbox' ) {

            $term_ids = array();

            foreach ( $field['inputs'] as $input ) {

                // Get term data by label name
                $term = get_term_by('name', esc_html($input['label']), $taxonomy);

                $term_name = $entry[ (string) $input['id'] ];

                // Get term id
                if ( !empty($term_name) )
                    $term_ids[] = (int) $term->term_id;

                $i++;
            }

            // Add selected types to post
            if ( !empty ( $term_ids )) wp_set_object_terms( $entry['post_id'], $term_ids, $taxonomy, true );

        }

    }

}