investment

I opened an investment account with old mutual last year and I was making payments to the account every week and when I went there to check this year the money I was putting in was not in my account after I lodged a complain they returned the money with no interest and the capital I invested is less by R1700.the staff members at old mutual Pongola have no answers to what happened to the money and the head office told me to wait for 5 work days. Im very disappointed with old mutual and thier staff. I want my full capital back