remove url field from comments form

Add the below code on functions.php

function alter_comment_form_fields($fields){
    $fields['url'] = '';  //removes website field
    return $fields;
}
add_filter('comment_form_default_fields','alter_comment_form_fields');

If not work, feel free to ask.
Note: Child theme is recommended to customize theme.

I have been pasting code but not deactivating jetpack….therefore, when I did this finally worked. thanks.