nittin vi ,
There are many circumstances / events which could cause the Green Droppings , worth considering before jumping to conclusions .
1/ Did the Birds miss a meal or two ?
2/ Could a pair be driving to nest so determinedly they miss feeding ?
3/ Could they be prevented from feeding ?
4/ Sudden change of Feed ?
5/ Try feeding 100% Peas for a couple of meals & note any improvement ?
If You are certain the above do not apply then You probably have a Health issue & are best advised to have tests carried out immediately by a Qualified Avian Vet , inform the Clinic about any products / medications or new Stock You may have introduced , the situation in the Loft , pairing , driving , laying or feeding Young , etc as some medications will affect the Breeding / Fertility temporarily .
Sometimes an Electrolyte Solution will bring about a change immediately .
You need to collect droppings BEFORE begining any Medication to prevent masking an accurate result .
Best Wishes ,
Steve....