Found the solution here (2014 year...)

https://intellij-support.jetbrains.com/hc/en-us/community/posts/206345169-Scrolling-with-keys-on-numeric-keypad-with-num-lock-off

it is very old bug. and solution is weird but working for me.

I just copy it here:

Go to File | Settings search for Keymap. Then at the right panel in the Editor Actions reassign Up, Right, Down, Left actions. Search for Up, right click and select Add Keyboard Shortcut. Then press any button and again press numpad Up button. Do the same thing for Right, Down and Left actions.