Poorest Service Ever Experienced

Where to start with Neotel / Liquid Telecoms. Basically it's a mess. Don't know how they run a business the way they do. Accounts added invoice items I don't understand. When I ask for evidence of costs I get no response. I can literally send 20 emails to sophia and get no response. She just does not care. I then did what was logical and cancelled with them and got an email from sinqobile that it will be cancelled by end of July. Still getting an invoice. When you ask why you get no response. I have experienced poor before but this!