Refund and poor response

I would like to express my bad service i received from CSI rental head office.I have proof of deposit of my second remote i already send to them and they do not want to refund me my R250.I was also change for replacement of i main door lock ,that i have reported and it was never fixed.All the rooms had keys which i returned and all the locks where working and i was also changed for replacement of the locks.I have escalated to Claire De vantier but she not willing to help me with this complains and i have also sent her the proof.