I he's an eye ring species, either a Fischer or Black Mask (otherwise known as personata lovebirds). I may be wrong, but he looks more like a Black Mask to me. It's very difficult to tell with color morphs, but I think Fischers generally have a smaller white collar than your guy has. Only my Masks have white chests like that. My Fischers also look a lot daintier than your bird. His feathers on his wings also reminds me more of my Masks than my Fischers, as they have entirely different feather structures. My Fischers have smoother looking feathers on their wings.
Is he banded? That might help you find hos breeder and what species he is.