Can't seem to ID this, taken at Iguazu Falls on the Argentina side in November 2018--note the yellow beak (not white or black) and the red under the rump. There is also a bib of bluish color below the neck, but not going as far as the chest. I checked birds of Brazil and Argentina, but didn't find a good enough match. Blue-headed parrot seemed closest, but for the color of the beak and the blue on these guys was not as vivid as blue-headed parrots seem to be. Can someone help?