I have a store installed with the following parameters:
Version 18.104.22.168 of Opencart. Version 2.2.31 of apache. Version 5.5.51-38.2 of MySQL and version 5.6.35 of PHP.
I am unable to view or edit any orders that have a completed or processed status. The only error message appearing in the opencart error logs is
2018-08-18 2:20:53 - PHP Warning: mysqli::query(): (21000/1242): Subquery returns more than 1 row in /home/.../system/library/db/mysqli.php on line 18
1. How can I resolve this problem, the Orders are in the database
2. How can I place opencart in a debug mode to dee the actual PHP-MySQL query string that is causing the problem?
Thank you for any credible help or suggestions.