Brand registry - cannot ammend my own products

I have uploaded a product using my own GS1 barcodes but every time i try to amend the product I get the following message * You are not approved to list this product and we are not accepting applications at this time. I am brand registered and have updated GS1 with the correct details of my amazon product but every time I try to do anything on my listing I get the same message above. Seller support are doing their usual chocolate fireguard impression telling me the same things again and again that the product is gated. Is there a process where I can get someone in amazon to tell me Why! or manage by brand and get this product live?