In 2002 I contracted with an architect to provide services in respect to putting an addition on our house -in the spring of 2003 all of the work done

The architect led me to believe he had received the letter of completion and there were no outstanding violations. In 2010 - 2011 we used the same architect to do another renovation job on the same property and in 2/2011 he informed me that he received the letter of completion for the 2010 - 2011 job. He also informed me that the 2002 job had outstanding plumbing violations concering filings with the city of NYC. I asked how that could happen since he was responsible to get a clean violation free completed job. He admitted his firm "Blew It". I am now being billed $600 for clearing up his error. Am I responsible for this bill almost 10 yrs latter? He had no idea there was a problem until I initiated the last job-and he assumed the 2002 job was completed and done. There was no mention of a violation between 2003-2011---Thank You