My lovebird is not masked; he is Fischer's blue mutation
I'm sorry but I beg to differ and will proceed to explain by using pics of my flock.
This is Penguin. She is a full blooded blue masked lovebird
Notice the rich and deep black colour on her head and face
Now look at my Sindel. She is a violet (blue series, white based) Fischer's lovebird.
She has faint grey on her head, and her cheeks and forehead are white. Those are the typical colours on a bue series fischer's lovebird.
Sindel again. You can see clear difference between Fischer's and Blue Masked
By looking at your lovebird's photo I see the rich deep black colour doesn't go all the way into the whole face like my Penguin does. It's very possible he is a hybrid cross between Fischer's and Blue Mask. But still he's gotten a lot more blue masked genes, I'd say he is 80% Masked (Aga****is Personatus, blue variety of Black Masked lovebird also known as a blue masked) and 20% Fischer's (Aga****is Fischeri).
EDIT: I should be able to fully write the scientific name of the species of lovebird...

"Agape" is love, "ornis" is the name for bird this is all in Greek language. Hence the translated name Lovebird for English speakers.