For private chat (private message) the text color is yellow

For guild chat the text color is green

For officer chat the name color is white

But there are many players who don't use or know about team chat in PvP (/team)
And those that do know about it don't use it because it's in the same color as regular chat.
Your team has no idea that it was sent in team chat so they reply in public chat

I suggest for a different color for team chat, possibly red