I just learned about these from Wirecutter which is the NYTimes version of Consumer Reports. From the article:
"Losing control of an online account to a digital intruder is a nightmare scenario. Multi-factor authentication (or MFA) is the best way to safeguard an account, because once MFA is enabled, an attacker won’t be able to access it—even if they have your username and password. A physical security key is the most secure MFA option, since it’s a dedicated authentication device and resistant to phishing. The Yubico Security Key C NFC is the best choice: It’s affordable and will work with just about every site that supports security keys. If you’re already familiar with security keys and need or want more-advanced features, the Yubico YubiKey 5C NFC is a more expensive yet worthwhile choice."
Yubico - YubiKey 5C NFC - Two-Factor authentication (2FA) Security Key, Connect via USB-C or NFC, FIDO Certified - Protect Your Online Accounts
A different but similar topic, I have been getting bombarded with 855 calls for 2 weeks, over 5 a day. I have been turning them off while calling.
iPhone will block unique numbers but I don't think it will block all 855 numbers. Anyone if it can?