Warning: Undefined array key "mkey" in C:\inetpub\wwwroot\ja\product\item.php on line 21

Fatal error: Uncaught TypeError: array_multisort(): Argument #1 ($array) must be an array or a sort flag in C:\inetpub\wwwroot\ja\product\item.php:42 Stack trace: #0 C:\inetpub\wwwroot\ja\product\item.php(42): array_multisort() #1 {main} thrown in C:\inetpub\wwwroot\ja\product\item.php on line 42