[Core2] make Button disappear

[wa-berlin]

I seek for a solution for the following problem.

The code below shows a button handling in Core2.
When the Event is detected I want to get rid of the button, i.e. make the button disappear.
I tried several options, see source code.
What happens is, that the event is disabled.
However when I push in the button area on the TFT the button appearance still behaves by changing colors.
What do I miss here?
Thank you in advance for any hints!

#include <M5Core2.h>

ButtonColors onCol = { TFT_DARKGREY, TFT_WHITE, TFT_WHITE };
ButtonColors offCol = { TFT_WHITE, TFT_BLACK, TFT_WHITE };

Button rt(162, 0, 158, 80, false, "120 sec", onCol, offCol);

void RtBtnTouched(Event& e) {
        Serial.println("Touched!");
		// deactivate button --> three approaches tested so far	   
		rt.delHandlers(RtBtnTouched); 
		rt.hide();
		~rt;		
}

void setup() {
	M5.begin();
	rt.addHandler(RtBtnTouched, E_TOUCH);
	rt.draw();
}

void loop() {
	M5.update();
}