Xbox One party chat always disconnects when 2 specific friends join

When 2 of my friends join a party together they disconnect, I've had other friends in the party as well as myself and our connection is stable. One friend has an open NAT type while the other is moderate, I've tried some stuff to get her an open NAT type
and nothing seems to work. Is it the NAT type messing with the party or is it something else.

:)

 

Why does it keep disconnecting the party?

When ever I'm in a party with a group of friend and another friends join the party it disconnect the whole party or just disconnects me and the person that join. It always keep doing this with same same person. It also happen with other of my friends. HELP!

 

Party Chat Disconnected, but only with certain friends Error Code 0x89231806

Hello,

I am experiencing problems when trying to chat in party with a specific friend. I am able to speak with anyone else whom I join a party with, but not a specific friend of mine. Sometimes it will work, but will disconnect again after playing for a while together.

The error code is 0x89231806 "party chat disconnected". Both of out NAT types are set to OPEN, I have reset my router, I have tried clearing my Xbox system cache.

Any help would be appreciated as this has been going on for weeks!

Thanks,

Nathan