Hmmm… that doesn’t sound right. Can you post some screenshots of what you are seeing and how it’s configured?
If you are getting actual Bermuda sensors for something, then it implies that it must either be set up in the configuration under Settings, Devices&Services, Bermuda, Configure, “Configured Devices” - or it must be a Private BLE Device in which case it will be saved in the config of that integration.
If it’s a random MAC address then it’s either sending iBeacon adverts (in which case it will be added via “Configured Devices” using the iBeacon UUID/Minor/Major, and/or via the Private BLE integration. Neither should require you to keep track of the MAC address, because it should just update the configured sensor whenever it knows something.
Unless of course you’re actually looking at a sensor provided by the iBeacon integration, in which case all of the above three posts can be ignored, and you need to add your thing via Bermuda, Configure, Configured Devices.
Some screenshots of what you’re seeing, and of your Bermuda configuration might be helpful if there’s any confusion