The swishing Frontier

I have a 2000 Nissan Frontier, 2wd, 4 banger. When I turn it on, it sounds like the belts are swishing, and it is hard to turn the wheel.

I took the truck in for work 6 months ago for the power steering pump. They told me it had water in it and needed to be replaced, which I had them do. The swishing sound wasn’t so bad then, and for a couple of months the power steering was fine, now it is as bas as it was when I took it in.

Any ideas?