Why is my imageview not changing in android studio app?

I am creating this app for school project that is supposed to show different icons based on the different Radio Buttons clicked. So in my layout I have an image View and in my codes I created a switch case to read the radio Buttons clicked. And of course I have an if-else statement underneath that links every Radio Button clicked to unique image that is supposed to appear in a row. However, by default it only executes the else statement, which it the "Others" option. So no matter which button I click, all the options only display the icon for Others. Anybody knows how can I solve this?