Yes, I didn't know there was an invasion when asked about Ukraine, but I knew about the past history. (some at least)
This is my point, it's easy to just not know something at any point in time, let alone some things you will only know if you have varying news sources, even if it's many years old.
How many of your friends, family and acquaintances know about the civil war in Ukraine for the nearly past decade?
But I had watched documentaries about Ukraine years ago, and since most people watch only Fox news, CNN, MSNBC, etc... they knew nothing at all.
So when Russia invaded most people were shocked, where I, and those few others that were information, were not as suprised.
Even the Russian soldiers who found themselves being sent into Ukraine were surprised.