Green’s Dictionary of Slang

business v.

[lit. SE do business (with)]

(orig. US black) to be concerned with, to be interested in.

[WI]M. Thelwell Harder They Come 331: I doan business wid all dat.
[UK](con. 1981) A. Wheatle East of Acre Lane 57: I don’t business how much money you mek.