Hello DAC3120,

We understand that your sbg6950ac2 device is assigning 192.168.0.252 IP and you're not able to find the device.

I would like to let you know that 192.168.0.252 is one of the private IP assigned to your device to communicate within the local network and using the following steps, you can find the MAC address associated with an IP address 192.168.0.252. By using the MAC address, you can identify the device.

1. Please connect any of your computer or mobile into your sbg6950ac2 Wi-Fi network and open a web browser like google chrome or safari.
2. Type in 192.168.0.1 on the address bar of the web browser
3.  Login into the page (Web interface) using the credentials.

Now you will be able to login into the web interface using the "default credentials".

1. Please select "LAN SET UP" Tab on the top menu

2. Tap on the "CLIENT LIST"

3. You will be able to view the list of devices that are connected to the gateway along with the IP addresses and the respective MAC Addresses.

like @SURFboard_Moderator says, the mac address can be used to identify it. 

You can try this site: https://maclookup.app/

The only issue you might see is apple devices lately have been using a random mac/ip address for “privacy” reasons. so it might not id the right device.