Sorry, but you don't give enough information on what you are trying to do !
What is this xpnl_card_header_touch2 ?
This looks like everything but not a Button_Click event !?
@DonManfred .. The issue has been resolved after 2 days of troubleshooting. It's my mistake that I didn't notice that tray is coming from background the reason I am not able to capture the click event of the button.