No service from VOX telecom

A few months ago we were interested in changing fiber service providers. We send emails and phone to try and get some answers from them. They don't reply to emails and when we called and spoke to the people at the call center, the only answer we got is that they are working from home and they will get someone to call us back. Well this never happened, then out of the blue I got an account for there fiber line, firstly it was never installed or activated at my premises and secondly the billing address is wrong. Thirdly I then did send an email to there Debtors Department and people they cc'd into the emails and also no reply from any of them, then I got another statement. This is when I don't know where else to turn too.