Laravel - whereHas checking latest record of a relationship without checking others

I have two tables that has One to Many relationship.

Bookings - (id)

booking_tasks - (id, booking_id,user_id)

one booking has many task one task has one booking

Booking Model:

 public function tasks() {
    return $this->hasMany('App\BookingTask');    
  }

BookingTask Model

public function booking() {
    return $this->belongsTo('App\Booking');
} 

I want to get list of bookings that, user_id = 2 for latest booking_task for the bookings. I do not want to check other old booking_tasks of the bookings.

ex:

I want to check whether the last record of the booking_task's user_id=2 then get it as a booking. In the example last booking_task's user_id = 5. So it will not get as booking.

My code is:

$bookings=Booking::whereHas('tasks',function($q){
            $q->where('user_id',2);//this will check whether any of record has user_id =2
})->get();

I used this also: But it is not a correct one,

$bookings=Booking::whereHas('tasks',function($q){
                $q->latest()->where('user_id',2)->limit(1);//this will check whether any of record has user_id =2 and return latest one.
    })->get();

Ho can I solve this problem, I have to use Laravel Eloquent also.

via Chebli Mohamed