Hitting Decisive Does NOT Work

I've been using decisive strike and in-game, I hit it right in the dead center, even giving off the sound that I actually hit it. After hitting it, it goes off cooldown as if I did and doesn't work at all. I went into Kill Your Friends even, JUST to test it and the five times that I tested it, it didn't work at all. Any ideas? Thanks guys.

It's a known bug that ds doesn't work in kill your friends, but in normal matches it's working fine. Probably you used it while the killer was already hooking you

Did you meet this problem with several killers, not KYF? I think that some host problems occured when you hit the DS. I face these problems, too. And the only way I found is just not using the DS.