Home Wi-Fi - Confused about unknown devices

[James011001]

Hi, I'm unsure about some of the "new devices on my home network.

Is it possible that there are different mac addresses due to the VPN being used?

In the list there were 2x devices with the same name, one was connected, the other was disconnected but had history earlier in the day.
They had different MAC addresses... neither of which match my flatmates. He's using the Kaspersky VPN - so I'm unsure if that's the reason?

Further, so I decided to change my WiFi password, now there are 2 devices that say "unknown device"... how am I to determine which is which? All our devices, except the TV box, now have Kaspersky Premium installed under the same account.

I'd like to ensure the TV box is correct because I can't install kaspersky on it. And I'd like to know which one is my flatmates phone.

Attached, the devices with different MAC addresses. ~20:13 was the time I installed Kaspersky on his device and connected him to the VPN

Edited 4 hours ago by James011001
getting facts straight

[James011001]

Worth noting, my flatmate isn't tech savvy, but he works for a call center and had to install an app they gave him. My feeling is if it's possible for the MAC address to be changed by VPN then it could still be his device that was connected at 16:27 - but it was through a VPN he just didn't know it.

At this point I'm not worried, new password would take centuries to hack. But I'd still like to be able to tag which is which with confidence so I can kick off any new devices.