Unauthorized purchase

In December last year I was in a Foschini store (Blue route Mall - Tokai, Western Cape) to do a bit of shopping. A consultant approached me telling me that if I wanted to get notifications when a purchase was made from my account I should complete a form which he handed me, which I completed and signed. Now this month upon inspecting my statement, I have apparently signed up for two insurance policies. Who gave them the right to sign me up for insurance policies? I already have these services from insurance companies and don't need them. I don't even know what these products cover nor am I interested. When I call the call center to complain, there's no one available, I'm transferred to somebody's voicemail. I'm stuck with services that I have to pay for (which I didn't ask for)... This is like buying insurance from a food outlet- you are not specialists in the field. You should stick to selling clothes.