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Fatal error: Uncaught TypeError: sqlsrv_query(): Argument #1 ($conn) must be of type resource, false given in C:\wamp64\www\ETKA\get_material_return_list.php:27 Stack trace: #0 C:\wamp64\www\ETKA\get_material_return_list.php(27): sqlsrv_query(false, 'SELECT \t\r\nmtr_m...') #1 {main} thrown in C:\wamp64\www\ETKA\get_material_return_list.php on line 27