Let me try to be helpful (rather than just insulting which for some reason is the go to reaction of so many people on these forums).
Make sure your FPS is as high as you can make it, if you miss one or two frames in Chivalry you can miss the windup of a fast weapon. This can make certain weapons appear to “invisible hit”. There are other threads about this if simply turning down graphics doesn’t work.
Some servers are laggy, especially on certain maps and you might see bad FPS drops. Find servers that are reliable.
Lastly check out youtube for some guides to combat, learning how to anticipate accelerated attacks and drags will help and you can learn some new techniques.