Hi,
Changing your Microsoft account password does not change your Windows PIN, so please first make sure you are using the correct sign-in method.
On the Windows sign-in screen, connect the laptop to Wi-Fi, then select Sign-in options > Password and enter your new Microsoft account password. Microsoft notes that an Internet connection may be required for sign-in in some cases.
If you normally sign in with a PIN, select “I forgot my PIN” instead. Changing the Microsoft account password does not automatically change the PIN.
If the Windows account is actually a local account rather than your Microsoft account, changing the Microsoft account password will not affect it. In that case, after entering the wrong password, select Reset password and answer the security questions.
Microsoft official instructions: Reset/change Windows sign-in password