how to find first owner in my iphone

I bought an iphone from a second party.

please help me for find a first owner

That is almost impossible.

Ask your money back if possible, perhaps you have bought a stolen iPhone.

If you can't get in touch with the previous owner / seller, you can't use the iPhone.

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See the following Apple articles:

Activation Lock for iPhone, iPad, and iPod touch

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

How to remove Activation Lock -> How to remove Activation Lock – Apple Support (UK)

• If you need help removing Activation Lock and have proof of purchase documentation, you can start an Activation Lock support request.

👉 Read this before you buy a 2nf hand iPhone.

You can also contact Apple support for help, -> Get Support (apple.com)

You have to show proof of ownership of your product, provide all documentation showing your purchase of the device.

If you do not have additional proof of ownership, contact the reseller. They may be able to provide the original purchase document.

Once Apple receive your proof of ownership, Apple will further review your request and provide an update.

See also -> Keep your receipt after you buy an Apple device

Keep your receipt after you buy an Apple device – Apple Support (UK)

No, as posted -> That is almost impossible.