Employer refused to pay my last salary, what are my options?

I need urgent help. I was working in a tech company in Bangalore and resigned last month. Despite serving my notice period, my employer is refusing to pay my last month's salary of ₹50,000. They claim performance issues, but I have met all targets. I've tried contacting HR multiple times but they are not responding. What legal actions can I take against my employer to get my due salary?