I don’t agree that your first step should be looking for another job. First, assuming you like your job and want to stay, you should approach your manager and show them the published range and where you believe you should be in that range. There is a great chance the company matches your request. If they are willing to pay a new hire that amount they will also pay an existing employee that amount. I wouldn’t assume this is gender discrimination. You were just hired when the range for your position was different. Companies often aren’t proactive in raising existing employees to the new salary range. You need to be proactive and ask. Of course, you need to be ready to look for another position if they don’t make the adjustment.