Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "kp_get_client_id" not found or invalid function name in /home2/apc2go/public_html/wp-includes/class-wp-hook.php:324 Stack trace: #0 /home2/apc2go/public_html/wp-includes/plugin.php(205): WP_Hook->apply_filters('', Array) #1 /home2/apc2go/public_html/wp-content/plugins/klarna-onsite-messaging-for-woocommerce/klarna-onsite-messaging-for-woocommerce.php(260): apply_filters('kosm_data_clien...', '') #2 /home2/apc2go/public_html/wp-content/plugins/klarna-onsite-messaging-for-woocommerce/klarna-onsite-messaging-for-woocommerce.php(80): Klarna_OnSite_Messaging_For_WooCommerce->set_data_client_id() #3 /home2/apc2go/public_html/wp-includes/class-wp-hook.php(324): Klarna_OnSite_Messaging_For_WooCommerce->init('') #4 /home2/apc2go/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #5 /home2/apc2go/public_html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #6 /home2/apc2go/public_html/wp-settings.php(559): do_action('plugins_loaded') #7 /home2/apc2go/public_html/wp-config.php(102): require_once('/home2/apc2go/p...') #8 /home2/apc2go/public_html/wp-load.php(50): require_once('/home2/apc2go/p...') #9 /home2/apc2go/public_html/wp-blog-header.php(13): require_once('/home2/apc2go/p...') #10 /home2/apc2go/public_html/index.php(17): require('/home2/apc2go/p...') #11 {main} thrown in /home2/apc2go/public_html/wp-includes/class-wp-hook.php on line 324