Hi VEsterly135 If the device you're seeing is an iOS device, it might be because of mac address randomization from Apple: To reduce this privacy risk, iOS 14, iPadOS 14, and watchOS 7 use a different MAC address for each Wi-Fi network. This unique, static MAC address is your device's private Wi-Fi address for that network only. https://support.apple.com/en-us/HT211227
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