Vumatel's Installation fee 1 year after installation

It has been a year since our Fiber line is installed. Now all of a sudden Vumatel is asking for R1700 for an installation fee. I went back and checked and the contract that I signed with my Fiber Provider explicitly says "FREE installation". Furthermore I have an e-mail from the Trustees of my Complex stating that Installation is Free. I responded 6 days ago to Vumatel with an extract of this contract. I haven't received a response and now my Fiber Line is down and it's not from my provider. Please can this be sorted out.