Abuse and exploitation by Mr D Food

Mr D Food is sending me promo emails daily. I sent numerous emails and even called them asking them to stop sending me those emails. They responded saying they will unsubscribe me but they keep on sending. Im staying in a village,U have never used their services and didn't subscribe to receive promos. Painful thing their emails consume my data on a daily basis. Everytime I switch on data their email comes in. It looks like they are desperate to recruit new customers since most of their existing customers complain about poor service. Im really tired of them exploitation my rights as a consumer even at the era of POPIA.