functions.php

<?php

// Add your own function to filter the fields
add_filter( 'submit_job_form_fields', 'remove_listify_submit_job_form_fields', 9999999999 );

// This is your function which takes the fields, modifies them, and returns them
// You can see the fields which can be changed here: https://github.com/mikejolley/WP-Job-Manager/blob/master/includes/forms/class-wp-job-manager-form-submit-job.php
function remove_listify_submit_job_form_fields( $fields ) {

    if( ! isset( $fields['company'] ) ) return $fields;

    // If phone, company_website, or company_video fields exist in company array, remove them
    if( isset( $fields['company']['phone'] ) ) unset( $fields['company']['phone']);
    if( isset( $fields['company']['company_website'] ) ) unset( $fields['company']['company_website']);
    if( isset( $fields['company']['company_video'] ) ) unset( $fields['company']['company_video']);

    // And return the modified fields
    return $fields;
}