What is the main job for a real estate title company?

I bought a real estate and there was a lien on it. we close escrow and now i find out that the lien has not been paid in full. I want to know who is responsible for this mess. I thought title company get paid to make sure you are buying a title free lien? Can somebody explain me whom do I have to go after? The lien was a HOA from the previous owner and the property was a short sale. The HOA demand was $3001 late fee. so we paid them but now the HOA is coming back and asking for attorneys' fee so they could remove the lien. I title or escrow or the HOA is the one in fault. Please let me know. Thanks