Quit salary without notice

I am running a service providing agency under Govt. sector. In Jan1 2018 a person age of 55 years approached us to work with. After a formal discussion of salary , hours, nature of job he decided to work with us and if found satisfactory then he will continue job. Then he come office sometimes late and observe the work, telling the past stories of employment. He commented he is observibg the job if he can do. We dont object him because we want a senior person to sit by. After 15 days of work he quit the job giving clause that he is not satisfied with the work. On mar 16 we got a notice from our govt office that the person is asking for salary why you are not giving it. But literally the person never approached and contacted for salary neither feel to finalised the salary on quit. I want to know how to give clarification that employee left job without giving any notice.