Job: Customer Service Supervisor (United States)

I'm highly trained in my workplace yet, the manager who controls the pay, gave at least two other employees, who happen to be male, higher pay for doing the same or less work than myself.

I know that employees beneath me are getting raises just to stay on or to meet the salary of another prospective employer, and the salaries are equal to my own! I've trained cashiers, Front End Supervisors and Managers who probably earn more than I do. I'm loyal to my company, I work very hard and have been rewarded with a pay raise which is almost an insult, given the work I do compared to many other associates. I have no advice but sure could use some because this just isn't fair and I really don't want to leave my job.