The icon is most likely hidden in the "overflow" menu.
Customize the taskbar notification area
The end user will need to change their settings to show your icon. You cannot do that via code or the setup, because it's up to the user to decide which icons appear on their computer.
If that's not
the problem, then you need to update your question to provide a clearer description of the issue, the relevant parts of your code, and what you have done to try to diagnose the problem.