How do I remove an unknown Apple ID from my iPhone?

If you can't get the person to sign out with their password then you will have to do activation lock removal with the original proof of purchase. See this article: How to remove Activation Lock - Apple Support

Review that article and at the bottom there's an area that says "start an activation lock request" --- click that.

If you are not the original owner Apple will not remove it.

Virgo_2024 wrote:

I’m trying to get signed back into my Apple ID can’t sign out of someone else’s Apple ID!!!

contact that someone else

This is crazy, talking about a “stolen iPhone” . 😡

I think that this is ridiculous talking about a “stolen iPhone”.😡

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