your/somebody's face doesn't fit

(one's) face doesn't fit

One's physical appearance or behavior is not well-suited for a specific job or task. That girl's pretty enough, but her face just doesn't fit for a couture ad campaign.
See also: face, fit

your/somebody’s ˈface doesn’t fit

used to say that somebody will not get a particular job or position because they do not have the appearance, personality, etc. that the employer wants, even when this should not be important: It doesn’t matter how qualified you are, if your face doesn’t fit, you don’t stand a chance.
See also: face, fit