Cancel my preorder

I am starting to get annoyed with Vox Telecom. I requested them to assist with activating my home fibre last week. Their atrocious service feels like a government department. I asked them to cancel my order and inform Zoom Fibre that I don't need their service anymore.

I can keep on being referred to another person who keeps on asking the reason for cancellation. They all promise to cancel until the next person calls and repeats the same question. All I need is for Vox to cancel my order. That is all I am requesting.