Awww, that's a shame. I do know it can taste pretty bad if you leave the bag in for too long. May take some experimenting with if you feel it might be worth perservering with.
Have you tried it with some CD berry flavouring. Just mentioned on another thread. Once you are allowed it, it's worth a try, rather than chucking the lot.
Considering Im not a tea drinker, I didnt actually mind green tea! I think I just got to the stage where Id rather have anything than another big glass of cold water!