Smart Shopper NO Response

I buy dog food monthly at PnP, and recently received a 100% off your next pedigree 6kg dry dogfood purchase voucher. Needless to say, Pnp have never heard of this, i was referred to Smart Shopper. On the phone I was told they have no such voucher. I've emailed them, with absolutely no response. This was last Friday. They probably won't bother getting back to me as the voucher expires end December. I mean did the voucher magically just appear? Thanks Smart Shopper, what a joke!