Subject — Interest is a service or a Good

Subject — Interest is a service or a Good

For any service, if the provider is trying to charge the “Late Payment Fee”, and on top of that late payment fee they are trying to levy 18% GST. Then my question is under Policy clarification that this “Late Payment Fee” is a service or Goods(Example Apartment Maintenance Services provided by builder not AOA / RWA)?

I see this neither as a service nor a Goods.