Regarding the problem that the click event only responds to double-click when set input mode game only.

Hello.
I am making a kind of keypad that uses click events in a game. However, when I set inputmode to game only, the click event only responds to double clicks only.
I have attached an image of how it looks like (the project is a test project)
If I take a video, the print string will not be displayed, so I only attached the image. Sorry.
This shows how the click is not responding and only the release is responding. (Normally, clicks and releases are displayed alternately.) Therefore, if the game mode is game only, the click event only responds to double clicks.
Also, if I add a widget to view port and then remove it for parnent, the same reaction occurs.
Is there any way to resolve this?

↓My program