Hi, I'm John! I will help you with this.
If the app comes back after a restart, it usually means something is adding it back automatically. This can happen because of a work/school policy, a manufacturer app, or the app itself after an update.
In the meantime, if you haven’t already already:
- Press Win + R, paste this, then press Enter:
%AppData%\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar - Look for the shortcut of that app and delete it.
- Then open Task Manager > find Windows Explorer > right-click it > Restart.
- After that, restart the PC and check if the app stays removed.
If it still comes back, please tell me:
- What app keeps returning to the taskbar?
- Is this a personal PC, or is it connected to a work/school account?
- Does it return right after restart, or only after opening that app?