Company not clearing salary arrears

So this lala shop that I'm working for wants to be a billion dollar company but doesn't believe in clearing salary arrears. This drama started around March this year just before the appraisal. The employee portal was shut down citing some "updates" and later they slyly updated terms and conditions related to appraisal in all of our offer letters. The outcome of this was although we were told that the salary was raised but we still received the old salary for 3 months (April, May, June). We were informed the arrears would be created by September. But no updates. It's November and still the HR is silent about the difference that they owe to us. What's the best way to tackle this situation? Of course I want to leave this company but not before I take my wages.