I want to change my Trusted device, I don’t know who the one on there now

Add or remove a trusted phone number

1. Go to Settings > [your name] > Password & Security.
2. Tap Edit (above the list of trusted phone numbers), then do one of the following: Add a number: Tap Add a Trusted Phone Number. Remove a number: Tap. next to the phone number.

Manage two-factor authentication for your Apple ID from iPhone