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The iPhone Privacy Warning message indicates that the device is using its original MAC address to join the Wi-Fi network, which could allow the network operator or other parties to track the device or profile its online activity. To prevent this, the device can use a different MAC address for each Wi-Fi network, which is called a Private Wi-Fi Address. This feature is enabled by default on devices running iOS 14 or later, but it can be turned off manually or automatically by some networks. To turn on the Private Wi-Fi Address, the user needs to go to Settings > Wi-Fi, tap the info icon next to the network name, and toggle on the Private Wi-Fi Address option. This will generate a new MAC address for the device and rejoin the network. References: = Use private Wi-Fi addresses in iOS 14, iPadOS 14, and watchOS 7, Wi-Fi Privacy Warning on an iPhone: What It Means & What To Do