Total scam operation. They ID themselves as Assistance Support Center. Some kind of group that can help you with your taxes if you owe in excess of $10,000. Sounds like a scam, but the accent suggests it's a domestic call. Can hear call-center noises in the background. Another site reported that they ask for you SSN# and bank account numbers. Total scam artists.
Anyone needing help with their tax liabilities should see an Enrolled Agent, or a CPA or an attorney specializing in tax law. Not some scammy cold-caller.