Objectivity is a central philosophical concept, related to reality and truth, which has been variously defined by sources. Generally, objectivity means the state or quality of being true even outside of a subject's individual biases, interpretations, feelings, and imaginings. A proposition is generally considered objectively true (to have objective truth) when its truth conditions are met without biases caused by feelings, ideas, opinions, etc., of a sentient subject.
If you accept that definition, then explain how morality meets that criteria. If you don't agree with it, then how are you defining it in the way you're using it?