I also have this problem but mine is different.
I switched to black to help out an alliance member .
Then I switch back into green . And my trade members are all green except for a black one.
My trade bonuses disappeared even though I am green which is the same as the other 4.
Jiang (Mathepid)
Date: 9/8/2007
(new team member)
No Team Bonus Sorry Urgent trade for another Awaiting Approval - Cancel <- Correct
Jiang (Mathepid)
Date: 9/6/2007
(team person 1)
No Team Bonus Back again! Approved - Cancel Wrong - same color
(team person 2)
Date: 8/19/2007
Jiang (Mathepid)
No Team Bonus Improved Foreign Relations Approved - Cancel Wrong - same color
(team person 3)
Date: 8/19/2007
Jiang (Mathepid)
No Team Bonus Trade Ring Approved - Cancel Wrong - same color
Jiang (Mathepid)
Date: 6/23/2007
(team person 4)
No Team Bonus Improved Foreign Relations Approved - Cancel Wrong - same color
^^^ if that make sense.
Regards
M.