Hi Arap,
Setting up a pin on your device makes it more secured. One important difference between a password and a Hello PIN is that the PIN is tied to the specific device on which it was set up. Read more in this documentation:
Thus, you still have option to remove it once you've done setting it up for the first time. Kindly follow the steps below:
- Open the Settings app, and click/tap on the Accounts icon.
- Select Sign-in options on the left side, and click/tap on the Remove button under PIN on the right side.
- Click/tap on Remove to confirm.
- Type in your Microsoft account password to verify, and click/tap on OK.
Additionally, you can refer answers mentioned in this thread:
Let us know how it turns out.
Note: Microsoft has updated the information in this reply to benefit users facing this issue.