What should I do with a 5 year old credit card debt that I am now being sued for by a Debt Management Co?

Had a company I own (my sole source of income) go through Bankruptcy Reorganization 4 years ago and because I was unable to pay myself for over a year I did not make any payments on a HSBC credit card for 6 months (balance under 4,000). When things started turning around, I called HSBC and they said they had written the debt off as bad and I would need to deal with however bought the debt. Every six months a different "Debt Management" company would call and I would send them a letter and ask for verification and proof they owned the debt. That would stop the action....until in December I received a letter from Nationwide debt Management that said I owed the debt. I request verification and they sent a letter on Jan 11 with HSBC account info and said I owe them $10,000+. I haven't heard from them since, but now they have filed a lawsuit against me. This is the 4th or 5th party after the original debt. Should I contact the Attorney to work out a settlement or make them proof it