Two of the air conditioner blows

Two of the 2000 model 206 on the driver's side of the 4 fan holes on the door, two of them are in the middle of the door.

It is because the air conditioning gas is getting low, my car had come under pressure in my car.

I wonder what it costs

Free if you have friends in industry. :)
Otherwise, 30-60 TL gas filling is done.
I don't know if the compressor oil change is necessary, I never changed it.