Insert into (Booking form)

public function insert(Request $request)
    {
        $vehicle_user   = Auth::user()->ic_number;
        $vehicle_status = 'Pending';
        $vehicle_name   = $request->input('vehicle_name');
        $event_name     = $request->input('event_name');
        $event_dest     = $request->input('event_dest');
        $book_time      = $request->input('book_time');
        $return_time    = $request->input('return_time');

        $overlap = DB::select("SELECT count(*) countid FROM vehicle_table
                    WHERE ('$book_time' < return_time)
                    AND
                    ('$return_time' > book_time)"
                  );

        $array = json_decode(json_encode($overlap), true);
        $count_data = $array[0]['countid'];

        if($count_data == 0)
        {
            DB::insert('INSERT INTO vehicle_table (
            vehicle_user,
            vehicle_name,
            event_name,
            event_dest,
            book_time,
            return_time,
            vehicle_status
            ) VALUES(?, ?, ?, ?, ?, ?, ?)', [
            $vehicle_user,
            $vehicle_name,
            $event_name,
            $event_dest,
            $book_time,
            $return_time,
            $vehicle_status,
            ]);

            header("Location: /vehicle", true, 301);
            exit();
        }

        else
        {
            echo "<script> if (alert('Invalid date. Please choose another date!'))
                            {
                            }
                            else
                            {
                                window.location.replace('/vehicle');
                            } </script> ";
        }
    }