mismatch of type of goods in invoice, e-way bill with physical verification - Goods and Services Tax - GST

Goods with vehicle detained, seizure order passed. Allegation is that quantity of goods same as stated in Tax invoice, e-waybill and in physical verification, officer found e-waybill, tax invoices, consignement note are in order, but type of goods not written properly in in invoice, e-waybill. Goods are MS Bar, TMT Bar and shutter profile, all goods rate @18%. Officer stated that goods ought to have written like M.S. Pati, Shutter strips, Side plate etc etc. My question is that RTP carrying goods with pro[er documents as per requirements of Rule 138 , quantity i.e. weight matched, but for type of goods not written properly by giving break up, for these reason penalty is legal? if I would write goods by break up then also same rate of goods, there was no evasion of tax. Moreover e-invoice generated already reflected in GSTR-1 . Kindly Answer by our Ld. experts.