Registration of service tax

Whether an assessee having a distributorship of sim cards & recharge coupons requires registration of service tax number? Acc to me it is under negative list issued recently. Here the company is asking for service tax registration number. Whether to fill “fill Non assessee” or file ST -1 “ form. What will be the category of the registrant & what will be the descripttion of taxable service.  In option only 1 option is there other than in negative list. Whether to check it or not????????