Accounts mess up

I have had Fibre with Afrihost for more then a year now, I keep on receiving invoices from Vumatel stating I owe them over R 1000 for the installation,I then call Afrihost to ask them why i am being invoiced from Vumatel for the installation and I get told that the invoice is for my records and that Afrihost will be paying for the installation, as it was part of the campaign they were running when I joined them, if I'm expected to pay for this "FREE" installation I am happy to cancel the fibre with Afrihost and join another service provider, I have been a great client to Afrihost always paying on time and no issues, please can this be resolved immediately and someone call me immediately.