It does happen Asth. It is very infrequent but it does happen. I actually notice it more on 1.26 than on 2.0.
Clearing cache, refreshing, etc. makes no difference, attack reports sometimes never show. I'm trying to remember but I can't be certain, that on Pi, I once didn't receive a defense report. However Pi is a 1.26 world and isn't for this forum.