Save Supermarket manager

Hi there..My name is Sphamandla Gwala from Pietermaritzburg, I worked at Save last year and I just left them in December last year so from that time I've been buying there, when I go to town because I've done nothing wrong to them, I never stole anything or fight anyone but yesterday I was shocked when the security told me that the Manager there told them not to allow me to come inside whether I came to buy grocery or anything, if I continue to come they must call back up for me like I'm some kind of ******** or danger to them.. please if there's anything you guys can do to teach this old man, who's a manager at Save Supermarket church Street in Pietermaritzburg, please help me because he has taken business and mix it with his hatred or made this personal..he hates me for leaving work now he doesn't want me to buy in the store..