Starbar QUICKSTRIKE Fly Bait Test 

You used it incorrectly. Use it dry and place on the ground level. Flies forage below 48” and rest above. You can make a paste and paint it on cardboard to dispose of it easily.

I found it works better dry.

What about knats

Saw some guy put bread on a plate with it and it killed a lot of flies

Add some coke, and it will amaze you