Unity Ui. Why constant pixel size option in Canvas Scaler don't work with mouse?

Hi. It’s hopeles to resolve this by myself.
I have a lot of buttons, dropdowns and Inputfields.
If I Choose “Scale with screen size” option in canvas scaler, ui works fine. But this lines do not draw the rectangle correct.
TrackerCenter.anchoredPosition = new Vector2 (Input.mousePosition.x-Screen.width/2, Input.mousePosition.y-Screen.height / 2);
If I Choose “Constaint pixel size” option in canvas scaler, ui looks correct. But mouse don’t hover and I can’t click any UI object.
Just look at this. What the problem.
https://youtu.be/EU57BPsy5C8

Anybody can help?