Display of branding name

sir, We registered a proprietorship firm under AP VAT act for principal commodity of "bullion and specie ". We opened a showroom exclusively for silver articles and silver jewellery . We plan to keep the gold artciles/gold jewellery in the showroom for sale purpose due to the slow movement of business for exclusively silver articles. We were migrated from AP vat Law to GST Law. As per our proposal, we don't want to new registration under GST law. Shall we continue the same business with external firm of New brand. We keep the only New Brand display board, but activities like invoices, billing , everything on the name of the registered firm. Can we take any permissions from any officials or shall we continue the business with new brand on behalf of registered firm . Please give your valuable suggestions