Serice tax on company residence for employees

I have given rented out two flats to a company XYZ Ltd. for exclusive use as residential purpose of their employees. This is also mentioned in the rent agreement. I have some other commercial property from which I am receiving rent and paying service tax. The service tax officer is now saying that I have to pay service tax on rent of these two flats from this company as the company(tenant) itself is a commercial concern. So indirectly it is used for commercial purpose. Please advice ?