First I'd make sure that you have not 'hard stapled it' to any of the fence posts and that the fence is straight to the sky and not to the floor (ie not up and down attached to the floor, you can fill any gaps under in with stones after) - (its the fence from the stays either end that keeps the posts up in the middle - not the posts in the middle keeping the fence up if you get my meaning).
Tighten the fence in the 100M only ramming the staples in to a point where they 'grip' on posts designed to take/stop movement. No good hard stapling to every fence post , makes adjustment hard at a later date, if the stay post goes it pulls all the fence over etc etc