Unable to activate a business account

I opened a business account via my mobile app, but at the last stage there was an issue. I did it via online banking and finally it registered the account and I received my debit card as well. When I tried to upload documents it failed. When I try to retrieve documents it also fails. After multiple calls and chats, I finally received an email address to send documents to, which is supposed to reply within 3 days. It is now 5 days with no reply or confirmation of the document verification. I cannot activate the account without verfication. A business co sultant even phoned me to ask how they can help. He just put me through to a back office team which do not answer the phone. I resent the documents again with same reply of 3 business days. I also checked and downloaded their how to guide which doesnt even have the correct email address! I even logged a query to which the reply was - this is an unattended mailbox. So where to now?