<ul><li>Fixed <strong>Undefined array key</strong> warning in <code>QuoteRequestModel.php</code> line 3031: changed bare array access <code>$cat_arr[$bidders_category]</code> to use <code>isset()</code> check before access</li><li>Fixed <strong>Undefined variable $label_arr2</strong> (line 3039): added explicit initialization of <code>$label_arr2 = array();</code> alongside other array initializations before the foreach loop — variable was only set inside the loop, causing Fatal error when RFQ data was empty</li><li>Root cause: both bugs triggered on page load AJAX call to <code>QuoteRequestController.php</code> (action: getChartData), PHP warnings were prepended to JSON output, causing <code>Unexpected token &lt;</code> JS parse error and broken chart rendering</li><li>Result: 0 JS errors, 0 PHP warnings, DataTables rendering correctly (9 tables), categories sidebar now populates</li></ul>