Mesh network drops when I move around

I just got a xfi gen2 pod to help coverage when in my basement.  I was dropping internet coverage on my phone when going into my basement - turning wifi on and off (on my phone) helps, but I am trying to avoid that.  I found this thread https://forums.xfinity.com/conversations/your-home-network/iphone-and-xfinity-mesh-network-connectivity-issue-xfi-pods-iphone/6815a28d9ad3b0659f08afe5 that seems to deal with this exact same issue and tried to use the solution.  However, when I try to change the security type, the only security mode available in the dropdown is WPA2.  How can I get the “WPA3-Personal-Transition” to be available for my network?