IPv6 setup on my Orbi RBR50 system

I was setting up my Orbit RBR50 system for IPv6 on Xfinity. I do not understand all the configuration options so I first did DHCP and got LPv6 working. However some apps on my phone kept losing connectivity to the Internet over and over afterwards. I read up on this a little more and set up IPv6 using Auto Config. Again lt works but now I do not have an IPv6 address on WAN? Is that how it should be? I'm trying to understand how this works so any information would be very helpful.