I am not sure how can black ink appear green (?) (it seems mission impossible task
. I can probably guess that may be other color (likely yellow ink) has cross contaminated as a result of failed cartridge. If this happen with DIY (do it yourself) refill kit, perhaps you have not refilled the cartridge properly.
If you consume a lot of inks and are benefiting from the savings and want to make another try, you can write email to me in private. Just let me know the cartridge you are using.