Re: Connecting to Ultimate Team is not possible at the moment.
Is your NAT type open or does it say UPnP unsuccessful?
I had this issue too, I looked into it, and I finally fixed it. I tried hooking up my series X to my PC via Ethernet and turned on my VPN on the PC, and it worked, so I figured it was some type of port forwarding issue because my UPnP was not open/successful according to my Xbox.
I have AT&T internet and I went into my:
1. Gateway settings URL (which should be located on your router (ex:https://192.xx.xx.xx))
2. Went to the firewall tab then selected NAT/Gaming, put the code/password in that should also be on your router
3. Under application hosting entry, Service: Xbox Series X, Needed by device: Your Xbox console/console name
4. I am not sure if this is necessary, but I added IPv6 Tunnel (6 in 4) (which you will find under services under "Application hosting entry" same place as step 3) and selected my Xbox as the "needed by device"
5. Just restart your Xbox, check your NAT type, and if it's open, then you should be good to go.