Hi Aminata,
Since you have already tried restarting and the Safe Mode options, I would not repeat those steps.
At this point, I recommend that you review and try the steps provided in the AI generated answer on your thread. That reply typically include the most relevant checks for this scenario.
On the sign-in screen, select Sign-in options and check whether a key-shaped Password icon is available. If it is, select it and enter the password for the account shown on the screen. Once signed in, open Settings > Accounts > Sign-in options > PIN (Windows Hello) and reset the PIN from there.
Please also confirm whether the account is a Microsoft account or a local account. The I forgot my PIN link at the sign-in screen is available only for Microsoft accounts, which may explain why the reset window is not completing. Also make sure the PC is connected to the Internet from the Network icon on the lock screen.
If no password icon appears at all, please share a photo of the available Sign-in options icons and the exact message shown after entering the PIN. Please hide the email address or account name before posting the photo. Thank you so much for your understanding.
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