Sounds from automatic gear

Just in the evening, when I parked the car I parked in the house and got the gear from P to R, there was a loud sneaking sound.

I walked the car for about 500 meters with this sound, although the car did not change the gears as it was going, there was no interruption of the ginning sound (as if rubbing it to the iron iron). When I bought it, there was nothing wrong with the vehicle's gearshifts.

What is this now ???