Can't focus keyboard from slider to parent button

I am making audio settings in which I made a button named “MasterVolume_Option”. On clicking this button the user will be able to change the value of the slider “MaVo_Slider” which is a child of the button. I made a blueprint, of which screenshot is attached below, in which on clicking or pressing enter on the button will let the user access the slider and when the slider has keyboard focus, pressing enter will lead to setting the keyboard focus back to the parent button. The problem is the On Clicked event of the button is working fine but the Enter pressed event is not executing. Any help would be very much appreciated

I am fairly new to Unreal Engine, so it would help a lot to get answers in simplified language.

I even tried using other keys as well like backspace and spacebar and if I put backspace for action mapping it still gives the same problem.

This is the screenshot of my slider settings. Any help would be appreciated.