Cannot Cross Fade with Logic...Help!

I was editing an audio track, and had no problem doing a couple of cross fades with the cross fade tool.

Then, all of a sudden it seems that the cross fade tool stopped working and I could not do a simple cross fade anymore. I quit the software and restarted the computer 5 times, and I'm still not able to use the cross fade.

Anyone has any idea of what the problem might be?

As you can see in the screeshot, at first, I was able to normally do the cross fade, but then on the last 2 regions, it just did not allow me to do it at all. It kept moving the region, and no cross fade. Really annoying.....

Thank you so much for your help already in advance 🙂