Vox Telecom - disgusting service and *********

I cancelled my fibre contract with Vox mid-month (April), meaning that I had to serve a 6 week notice period until end of following month (May). Vox communicated that they would arrange collection of their router after that period had passed. I had subsequently already moved to my new provider. I then received no further contact from Vox until receiving an account on 24 June for "non returned hardware". I queried this with their accounts team and explained teh situation/confusion and was told that it was too late for them to cancel the debit order but that I was welcome to reverse it with my bank, which I did. They requested that I arrange delivery of the router at my own cost, which I refused. and they stated that they would be following up with their courier to arrange collection and would get back to me. They never did. I have followed up with multiple calls and emails with no response to mail, and phone calls ending with someone promising to get someone else to call me back and then never hearing anything back. All the while receiving account mails for an overdue account and having additional admin fees attached. Today I was contacted and asked when I would be making payment as they are in the process of handing me over to their attorneys. On this call the accounts person has said they could see that my latest request for contact is still sitting unattended on their system and would get someone to call me back. I continue to wait. I'm absolutely disgusted by their shocking customer service, lack of internal communication and general dishonesty.