Note the software wont simply uninstall if it included Family Protection, Parental Controls or Anti-Theft.
In the case of the first two you would need the user name and password for the Administrator who set them up. If the last one it can't simply be uninstalled without a lot of security measures as it is designed to prevent theft.
Technical Support can help with that, they are available free of charge by phone or online chat and linked under Useful Links at the top of this page.
If none of those were installed and the software simply wont uninstall, maybe because of corruption, you can uninstall it using the MCPR tool
but as you have already tried that best to call Technical support via the link in my signature below.
Have you tried uninstalling when in safe mode?
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