No Option to Disable AP Isolation

Hello,

My Chromecast very recently refused to connect with my WiFi extender, it had worked previously for best part of a year. I have logged into Netgear Genie and have so far been unable to find an option to disable AP Isolation or Guest Mode. Is this option not available with this particular extender? As mentioned, the Chromecast previously worked with this extender without any problems for a reasonably long time.

Apologies if this topic has been discussed previously, I was unable to find any discussions for my exact situation.

Many thanks.