Utilization of credit of s.tax paid on sales commission.

Dear friend,

My company is manufacturing greases and to sale the grease we pay sales commission and service tax thereon. We availed & utilised the service tax as input service under rule 2(l) of CENVAT Credit Rules 2004. But the dept give me a show cause notice for wrong utilisation of credit. The state that as it is not qualified as input service as this is not relating to manufacture of final products and that can't be a sales promotion exp.

They demand the duty with penalty.

So my friends please suggest me what should I do.

Regards,

Milan Das.