3. Log in to your mobile phone carrier account and enable a an account PIN or passcode. The PIN must them be supplied for any future account changes. This will make SIM-swap attacks against you more difficult.
(Incidentally, this is one of the reasons you really don't want to use SMS as your 2FA method, unless you have no other option.)
https://www.wired.com/story/sim-swap-attack-defend-phone/
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