Sharing location using Find My from my new iPhone show location of my old iPhone.

• Multiple Devices: To share another device's location, you typically need to have more than one Apple device in your account. This could be an iPhone, iPad, or Mac.
• Single Device: If you only have one Apple Device (iPhone iPad, Mac), then that's the only device associated with your Apple ID. In this case, there wouldn't be another device to choose from for location sharing of the device.

Choose which device to share your location from

You can share your location from a different device. For example, if you share your location from an iPad, you can share your location from an iPhone that you own instead.

1. On the iPhone or iPad that you want to share your location from, open the Settings app.
2. Tap your name.
3. Tap Find My.
4. Tap Use this [device] as My Location.

Share your location with your family - Apple Support

Dana_33 Said:

"Sharing location using Find My from my new iPhone show location of my old iPhone.: I gave my old phone to apple (named Dana!) and i got a new iphone but when i try to share my location it tells me it is using the location of my old device. I erased my old phone on Find My and I changed the name of my new phone."

-------

Thank you for the screenshot.

Properly Selling an iPhone:

Why the issue?

You likely never disassociated this from your Apple Account. So, get the phone back, and then perform as instead here, including the iCloud logout: What to do Before you Sell, Give Away, or Trade in your iPhone or iPad - Apple Support. You'd then be safe from there.