PP discharge?

So I had a baby 4 months ago. C section.

I am breast feeding and on the pill. Also haven’t had my period yet. For the last two months I have been having a large amount of sticky thick discharge. No itching or burning. It has a weird green tint to it. I’ve been to the doctor and all tests come back negative and that everything is normal... has anyone else had this kind of discharge after giving birth?