There's no such thing as Black-faced. Black-cheeked have a lot less black than Black-masked, which are the second commonest lovebird species in aviculture [after Peach-faced], and the rump is a different colour. This one looks too orange about the face to be pure Black-cheeked, and I suspect has Fischer's in its ancestry.
Looking at it again, it could be a 'yellow' Black-cheeked, but this wopuld again suggest hybrid ancestry. A lot of Lovebird species are hybridised in the process of 'transferring' colour mutations from one species to another. A recessive mutation could lurk in a population for years without producing a visual mutant. OR it could be a spontaneous mutation of a yellow Black-cheeked..........
