Strange rotation issue when recording animation

Hi everyone!
I'm a beginner at Unity and I was doing pretty well at animations.
I was working on an bone animation of my character and, suddenly, it started this strange behavior when traying to make the interpolation. All that I was used to do until now, seens not to work anymore.

I have searched all over the web but didn't find any tip on how resolve this. And I can't remeber if I made some change that caused this. Bellow it's a recording of my problem: