Fatal error: Uncaught Error: Class "Plot" not found in C:\xampp\htdocs\rp_backend\vendor\mitoteam\jpgraph\src\lib\jpgraph_contour.php:389 Stack trace: #0 {main} thrown in C:\xampp\htdocs\rp_backend\vendor\mitoteam\jpgraph\src\lib\jpgraph_contour.php on line 389