Closing/killing applications in Linux Mint (Cinnamon)

I recently switched to mint (Cinnamon 4.4.8) and having hard time closing applications. I had ubuntu 20.04 and installed cinnamon DE over it.

When I try to close some applications it gets closed but does not go away from the bottom menu bar. Menu bar shows the application as open but when you click on it, neither the existing (closed but showing) window opens nor a new window opens. I have to right-click and start a new window of the application. Moreover, right-clicking and closing all instances of application do not work either. Some of these closed applications do not show up in the running processes.