I saw in the thread that @Leebo linked that he means spelling errors in the reading. I don’t think there is any lenience there and I don’t want there to be any. And expecting the staff to reset your vocab for you manually is kind of silly. The override script was mentioned in the other thread, but no link was provided.
So, @Sutho81, here’s the override script: [OBSOLETE] Wanikani Override ("ignore answer button")
It allows you to ignore your answer and try again. (I think, I haven’t used it myself)
And here are instructions on how to install it: Visual Guide on How To Install A Userscript
I hope that makes your WaniKani experience more to your liking.