Title: Fatal error: undefined function pt_unserialize_to_array()
Last modified: September 4, 2026

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# Fatal error: undefined function pt_unserialize_to_array()

 *  [Jos Klever](https://wordpress.org/support/users/josklever/)
 * (@josklever)
 * [4 days, 7 hours ago](https://wordpress.org/support/topic/fatal-error-undefined-function-pt_unserialize_to_array/)
 * With version 5.0.4 I get a fatal error:
 *     ```wp-block-code
       PHP Fatal error:  Uncaught Error: Call to undefined function pt_unserialize_to_array() in /.../wp-content/plugins/paytium/includes/notification-functions.php:21Stack trace:#0 /.../wp-content/plugins/paytium/class-paytium.php(712): paytium_add_notification()#1 /.../wp-includes/class-wp-hook.php(353): Paytium->includes()#2 /.../wp-includes/class-wp-hook.php(377): WP_Hook->apply_filters()#3 /.../wp-includes/plugin.php(523): WP_Hook->do_action()#4 /.../wp-settings.php(779): do_action()#5 /.../wp-config.php(101): require_once('...')#6 /.../wp-load.php(50): require_once('...')#7 /.../wp-blog-header.php(13): require_once('...')#8 /.../index.php(17): require('...')#9 {main}  thrown in /.../wp-content/plugins/paytium/includes/notification-functions.php on line 21
       ```
   
 * This happens, because the function `paytium_add_notification()` is called while`
   includes/payment-functions.php` hasn’t been loaded yet.
 * As a quick fix I’ve added this at line 689 of class-paytium.php:
 *     ```wp-block-code
       include_once( PT_PATH . 'includes/payment-functions.php' );
       ```
   
 * I know it’s loaded a bit further down the file, but it shouldn’t hurt because
   of the `include_once` and it’s clear the order is not correct.

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Thread Starter [Jos Klever](https://wordpress.org/support/users/josklever/)
 * (@josklever)
 * [4 days, 6 hours ago](https://wordpress.org/support/topic/fatal-error-undefined-function-pt_unserialize_to_array/#post-19012002)
 * This site is also using **Mollie Payments for WooCommerce 8.1.9** and I think
   that this is creating some conflict, causing the notification that’s actually
   not shown in the dashboard.
 * On another site there was no error, but it doesn’t have Mollie Payments for WooCommerce
   installed.
 *  [bramdehaan](https://wordpress.org/support/users/bramdehaan/)
 * (@bramdehaan)
 * [3 days, 11 hours ago](https://wordpress.org/support/topic/fatal-error-undefined-function-pt_unserialize_to_array/#post-19012398)
 * I can confirm this issue (also with Mollie), and also confirm the fix by [@josklever](https://wordpress.org/support/users/josklever/)
   worked: thanks a bunch!.

Viewing 2 replies - 1 through 2 (of 2 total)

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 * 2 replies
 * 2 participants
 * Last reply from: [bramdehaan](https://wordpress.org/support/users/bramdehaan/)
 * Last activity: [3 days, 11 hours ago](https://wordpress.org/support/topic/fatal-error-undefined-function-pt_unserialize_to_array/#post-19012398)
 * Status: not resolved