Awesome, but huge problem

First of, l love this app, really affective way to learn a new language! I am learning Italian and German. But today, when I was practicing Italian, it told me my answer was wrong, but I was right, so I hit the "my answer was right" button. But then, later, it told me the same question! I told the same right answer and again, it said NO!!! And it did that 10 times, so please, fix it. Other than that, I suggest you get the app, it is awesome!?????

War leader about Duolingo Learn Many Languages for Free, v5.0.15