Trout aren't real. Have you ever watched fly fishermen? The hook barely even touches the water!
You've been watching the wrong fly fishermen.
You need to let the fly float down across the top of the fish from further up the river, once it's passed your target area you re-settle it upstream and wait till it floats passed again. You don't flick the water with the fly all the time cos' that just scares them away. (although farmed fish can be caught like this on occasion, but only if they're new to the river).