Neotel bills me while i dont have a service

I approached Neotel when I didn't received the sufficient coverage from my previous adsl supplier - I was also porting my landline and everything - when I signed the deal I notified the Sales Person Ayanda that I need everything the moment that my current contract expired - they delivered very fast the device but I couldn't use it till my adsl is switch over and ported as well as my new adsl is installed - this was also one of my instructions that I will be using neotel then- my contract exp and I asked for the line to be ported the technicians came and said I have no infrastructure where I cancelled the contract and they picked up the device but I get billed for a service which I don't have infrastructure or service - and when I queried my billing there response is \Please note as the service is over the 7 days grace period we cannot credit the invoice"- it isn't my fault that Neotel cant provide a service and Ayanda told me that I wont be billed before the port is taking place - I want these two invoices credited and a refund for the first invoice and my last invoice not debited"""