The Xbox part chat only works if its just me and one other person

Xbox chats are private as its only you and the other person who can veiw the messages

Hey there,

Party chat is where you can have multiple people in a chat, talking, at the same time. Private chat is where it is only you and one other person. This makes it more private for you and the other person as you can not have more then two people in the chat.
This will be between you and a friend only.

As for why this feature is not supported on the Xbox One. In short, I don't know. This could be because of how many people used the feature or how the feature worked. If you would like this feature on Xbox One, then you can make a suggestion on the Xbox
feedback website:

http://xbox.uservoice.com

I hope this helps you,

Regards,

I'm not aware of a glitch that allows you to use party chat but, if you want to talk with just one other person, you can use Xbox live private chat.

Hi. I am also having party issues. Everyone in the party can hear me, I can't hear anyone

Can you help?

Hi, since we now know you've recently had a communications ban, it's possible that you're being affected by a glitch in the system which stops recently banned players from being able to communicate after their ban has been lifted.

The enforcement team are working on a fix.

Please check out this thread for information and steps that might help:

forums.xbox.com/.../2050832.aspx