I am getting undefined variable from the ADmin area in WordPress [duplicate]

/home/trave488/cambridgenigeria.com.ng/wp-content/plugins/ijmbcenters/ijmbcenter.php on line 201

Warning: Undefined variable $entry_id in /home/…….php on line 201

Here is my code.

function custom_users_table_column($value, $column_name, $user_id) {
     $user = get_userdata( $user_id );
       if ( 'admission_letter' == $column_name ) {
    if( check_parent_guardian_form_submit($user_id)){
        if(get_user_meta($user_id,'entry_id',true)){
            $entry_id=get_user_meta($user_id,'entry_id',true);
            $status = get_gf_form_fields_value_by_id($entry_id,225);          
        }
    }else{
        $status=get_user_meta($user_id, 'registration_payment_status', true);
    }
    if($status=='Paid'){
        return '<button class="submission_letter" data-user_id='.$user_id.' data-entry_id='.$entry_id.'>Mail Admission Letter</button><button class="view_submission_letter" data-user_id='.$user_id.' data-entry_id='.$entry_id.'>View Admission Letter</button>';
    }else{
        return 'Not Paid';
    }

}

I am using Gravity Form plugins to echo the form for the form to be printed by users.

The issue is error handling if the field is empty, but I don’t know how to go about it, when a field is empty is supposed to be blanked,and not to bring it error.