I was a complainant in one criminal case in my previous company. I left that company four years ago. Now I have received a subpoena from the court in that matter to appear before the court for evidence. Since I left that job four years back, I don't posess any document and/or information related to that case. Moreover I relocated to other place. What should I do? Whether it is necessary for me to comply with the subpoena? Is it necessary for me to appear in person before court?