UNCLAIMED BENEFITS

I received a call from a tracing company, followed by an email, regarding unclaimed benefits from a provident fund that I belonged to. The tracing company asked me for my bank details, identity number and other personal information. They attached a Sanlam Retirement Fund form. As I have no idea who the tracing agent is and whether I can trust them, I tried to contact Sanlam directly by dialling their customer care number (***). I tried this four times, only to be cut off at various stages. First of all, a call centre should not cut off clients and secondly, where a company hired a tracing agent to find individuals, the actual transaction for the payment of unclaimed benefits should be between the client and the Fund (Sanlam)? Unfortunately I have no way of verifying the information because Sanlam's call centre line cuts me off! I am dying to know whether there is a **** going on or whether this is a legitimate request.