Laravel considering variable as column name in query builder

I am using laravel 5.5 and checking event checking if slot available between 2 times using this query:

$schedules->where('id', $id)
                ->wherebetween($date, ['start','end'])
                ->orwherebetween($endTime, ['start','end'])
                ->orwherebetween('start', [$date,$endTime])
                ->orderBy('start')->get(); 

getting this error

"message": "SQLSTATE[42S22]: Column not found: 1054 Unknown column '2019-03-06 13:00:00' in 'where clause'

via Chebli Mohamed