"Contact the previous owner and ask them to follow these steps to remove the device from their account:
1. Sign in to their iCloud account at www.icloud.com/find.
2. Click All Devices to open a list of devices linked to their account, then select the device to be removed. It should show a gray dot or the word “Offline” next to the device name.
3. Click "Remove from Account" to remove the device from their account.
After the device is removed from the previous owner’s account, turn the device off by pressing and holding the Sleep/Wake button located on the top-right side of the device. Then restart your device and proceed with device setup as you would normally."