No way to move down the pop-up by K-AI

I was using an Expression node to create an age group. I used K-AI to generate if statements (described three groups and their ages) and click, then a pop-up showed up but the pop-up was half above my screen and I had no way to move it down. /

Long times ago, the similar symptom occurred when I clicked on the table icon in the node output monitor, the half of the pop-up screen was located above the screen, I had difficulty to move it down as I had no way to click the top part of the pop-up screen.

Any suggestion would be appreciated.