WHMCS stop renewal invoice creation if unpaid exists for a service.

[ambaha]

How to prevent WHMCS from generating duplicate invoices for the same service renewal?

We are currently facing an issue in WHMCS (version 8.x, PHP 😎 where multiple invoices are generated for the same service during the renewal process. Here’s the scenario:

1. A renewal invoice is created but remains unpaid.
2. When the client clicks the “Renew” button again, WHMCS generates a new invoice and cancel Previous invoice, even though an unpaid invoice already exists for the same service.

This behavior clutter in the system. My goal is to prevent WHMCS from generating a new invoice if there is already an unpaid invoice linked to the same service or product.

I use this hook but problem not solved.

 

<?php

use WHMCS\Database\Capsule;

add_hook('InvoiceCreation', 1, function($vars) {
    $relid = $vars['relatedid'];
    if (empty($relid)) {
        return; 
    }
    $unpaidInvoice = Capsule::table('tblinvoices')
        ->join('tblinvoiceitems', 'tblinvoices.id', '=', 'tblinvoiceitems.invoiceid')
        ->where('tblinvoices.status', 'Unpaid') 
        ->where('tblinvoiceitems.relid', $relid)
        ->exists(); 
    if ($unpaidInvoice) {
        throw new \Exception('An unpaid invoice already exists for this service. Please pay it first.');
    }
});

 

 

Edited Sunday at 08:16 PM by ambaha

[We Connect Nordic AB]

Hello

Hope this code fixes the issue

 

<?php
/**
 * prevent_duplicate_renewal.php
 *
 * Prevent WHMCS from generating a new renewal invoice when
 * an unpaid one already exists for the same service.
 *
 * Drop this file into includes/hooks/ and WHMCS will pick it up.
 */

use WHMCS\Database\Capsule;

add_hook('InvoiceCreation', 1, function($vars) {
    // Only act on client-area triggered renewals
    if ($vars['source'] !== 'clientarea') {
        return;
    }

    $invoiceId = $vars['invoiceid'];

    // Fetch all hosting/service items on the newly created invoice
    $items = Capsule::table('tblinvoiceitems')
        ->where('invoiceid', $invoiceId)
        ->where('type', 'Hosting') // for addons/domains you may need 'Addon' or 'Domain'
        ->get();

    foreach ($items as $item) {
        $serviceId = $item->relid;
        if (!$serviceId) {
            continue;
        }

        // Is there another unpaid invoice for this exact service?
        $duplicateExists = Capsule::table('tblinvoices')
            ->join('tblinvoiceitems', 'tblinvoiceitems.invoiceid', '=', 'tblinvoices.id')
            ->where('tblinvoices.status', 'Unpaid')
            ->where('tblinvoiceitems.relid', $serviceId)
            ->where('tblinvoiceitems.invoiceid', '!=', $invoiceId)
            ->exists();

        if ($duplicateExists) {
            // Cancel the just-created invoice
            Capsule::table('tblinvoices')
                ->where('id', $invoiceId)
                ->update(['status' => 'Cancelled']);

            // Log for your reference
            logActivity(
                "Prevented duplicate renewal: cancelled invoice #{$invoiceId} for service ID {$serviceId}"
            );

            // No need to check further line items
            break;
        }
    }
});