Hello, thank you for reaching out to Microsoft Q&A.
May I please know if you have the option to reset your PIN from the Sign-in Options screen?
Select the "I forgot my PIN" option on the sign-in screen and follow the prompts to reset it.
Reference:
Change or reset your PIN in Windows
If I forgot my PIN, the PIN option is not available. Switch the Sign in option from PIN to Password and sign in with your Microsoft account password.
Let me know if you still need more help.