Hello,
Thank you for posting in Q&A forum.
You can try to delete the PIN using the I forgot my PIN option in Windows 11, as follows:
Press Win+I to open Settings, then open the Accounts tab, then click Sign-in options, expand the PIN (Windows Hello) option, click I forgot my PIN option, confirm and enter your Microsoft account to log in, and finally click Cancel when the dialog box for setting a PIN appears.
I hope the information above is helpful.
Best regards
Zunhui
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