Many carriers let you set an "account password" or "account pin" - changes can't be made to the account without it (even with personal info like SSN, bday, etc)

Financial institutions offer it to sometimes - my credit union requires the account password, or a visit to a branch to show ID - no amount of personal info will allow you access.

Any carrier will allow you to change your password or pin using other information .

Otherwise, what would happen in the frequent case where users forget their pin?

> Any carrier will allow you to change your password or pin using other information .

If by "other information" you mean "come into a store and show a government issued photo ID" you are correct. That's a fairly high bar to clear.

That's the way my carrier does it, and I assume if they violate their own procedures I could evaluate my legal options... though as a practical matter I use a VOIP # which requires a 2FA protected login to port out for vendors that force me to use SMS 2FA.

Which carrier is that?

Or allowing one to "confirm" their accoubt via SMS if they've lost the TOTP code generating device.

(Because no one would lie about that)

Use a different financial institution