无法运行查询：Connection.php第673行中的异常：SQLSTATE [42000]：语法错误或访问冲突：1064

I'm building a laravel application where there is a controller which functionality is we have to book a classroom where if a time has already booked or there in database we can't book a classroom in that time interval. I have used the following controller :I'm building a laravel application where there