Warning: Undefined array key "ecproductcart" in C:\xampp\htdocs\bluecom_new\application\front\cart\index.php on line 18

Fatal error: Uncaught TypeError: array_diff(): Argument #1 ($array) must be of type array, null given in C:\xampp\htdocs\bluecom_new\application\front\cart\index.php:18 Stack trace: #0 C:\xampp\htdocs\bluecom_new\application\front\cart\index.php(18): array_diff(NULL, Array) #1 C:\xampp\htdocs\bluecom_new\index.php(46): require('C:\\xampp\\htdocs...') #2 {main} thrown in C:\xampp\htdocs\bluecom_new\application\front\cart\index.php on line 18