how can I unlock my second iphone ?

Hello there khajag, Great! Download iTunes on your computer. Make sure to follow all the steps listed in the article correctly. If you need any more help make sure to reply to my comment have a great rest of your day! If you forgot the passcode on your iPhone, or your iPhone is disabled - Apple Support

Hello, khajag256

What do you mean by a lock? Do you mean iCloud activation lock or passcode lock or carrier lock?

See the Apple Support article(s) below.

Passcode - If you forgot the passcode for your iPhone or your device is disabled.      

How is it locked? Activation Lock? Passcode locked?

Can you attach an image, please?

Ok do you have a computer you can access right now?

Try to follow all of the steps from Eric Root.

See the link I posted above.

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