Illegal offset products

Hi,
Am using twint payment gateway, while doing checkout with live payment integration, am getting the “Illegal offset products”. In the error log am getting the below error. But it works fine using the test payment integration. So please give the solution asap.

[error] Customweb_Mvc_Controller_Dispatcher: Illegal string offset ‘products’
Illegal string offset ‘products’
#0 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/purchase-log.class.php(354): Customweb_Core_Util_Error::handleErrors(2, ‘Illegal string …’, ‘/var/www/dev/la…’, 354, Array)
#1 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/product.class.php(655): WPSC_Purchase_Log::get_stats_for_product(3238)
#2 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/product.class.php(304): WPSC_Product->process_stats()
#3 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/product.class.php(330): WPSC_Product->_maybe_lazy_load_property(‘sales’)
#4 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/stats.functions.php(40): WPSC_Product->__get(‘sales’)
#5 /var/www/dev/lafinesse/wp-includes/class-wp-hook.php(288): _wpsc_action_update_product_stats(‘4’, 6, ‘1’, Object(WPSC_Purchase_Log))
#6 /var/www/dev/lafinesse/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters(”, Array)
#7 /var/www/dev/lafinesse/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#8 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/purchase-log.class.php(1040): do_action(‘wpsc_update_pur…’, ‘4’, 6, ‘1’, Object(WPSC_Purchase_Log))
#9 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/purchase-log.helpers.php(96): WPSC_Purchase_Log->save()
#10 /var/www/dev/lafinesse/wp-content/plugins/wp-e-commerce/wpsc-includes/merchant.class.php(310): wpsc_update_purchase_log_status(‘4’, 6)
#11 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/classes/TwintCw/Entity/Transaction.php(64): wpsc_merchant->set_purchase_processed_by_purchid(6)
#12 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/classes/TwintCw/Entity/Transaction.php(39): TwintCw_Entity_Transaction->forceTransactionFailing()
#13 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Database/Entity/Manager.php(281): TwintCw_Entity_Transaction->onBeforeSave(Object(TwintCw_EntityManager))
#14 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Database/Entity/Manager.php(52): Customweb_Database_Entity_Manager->callBeforeSave(Object(TwintCw_Entity_Transaction))
#15 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Payment/TransactionHandler.php(168): Customweb_Database_Entity_Manager->persist(Object(TwintCw_Entity_Transaction))
#16 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Payment/Endpoint/Dispatcher.php(84): Customweb_Payment_TransactionHandler->persistTransactionObject(Object(Customweb_Twint_Authorization_Transaction))
#17 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Mvc/Controller/Dispatcher.php(101): Customweb_Payment_Endpoint_Dispatcher->postProcessActionInvocation(Object(Customweb_Twint_Endpoint_Process), Object(ReflectionMethod), Array, Object(Customweb_DependencyInjection_Container_Extendable))
#18 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Payment/Endpoint/Dispatcher.php(65): Customweb_Mvc_Controller_Dispatcher->invokeControllerAction(Object(TwintCw_ContextRequest), ‘process’, ‘template’)
#19 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/lib/Customweb/Mvc/Controller/Dispatcher.php(81): Customweb_Payment_Endpoint_Dispatcher->invokeControllerAction(Object(TwintCw_ContextRequest), ‘process’, ‘template’)
#20 /var/www/dev/lafinesse/wp-content/plugins/ecommerce_twintcw/endpoint.php(49): Customweb_Mvc_Controller_Dispatcher->dispatch(Object(TwintCw_ContextRequest))
#21 {main}

object(TwintCw_ContextRequest)#1 (0) {
}

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