Pathetic customer service by Pick n pay manager

I want to raise a complaint regarding the calibre of store managers at Pick n Pay Rondebosch, particularly one by the name of Gerry (on duty at 16h30) on the 17th of March 2019. I want to point it out that Gerry needs some customer service schooling for someone in her managerial position in order to deal with customer queries satisfactorily. I was at pick and pay today and wanted to redeem a smart voucher which was in my pocket and was expiring today but forgot my wallet which has my smart shopper at home. On the voucher threes no stipulation that you should have your card present when redeeming the voucher, which if thad been clear all this unfriendly encounter with Gerry. She could not explain to me why i could not redeem the voucher and started attacking my personality, which i did not appreciate, further more she walked away in the middle of the conversation which was very rude for a manager to do. When i asked to speak to her before i left the shop she refused to come to the shop front. I am only raising this because my fear is that Pick n pay may loose customers because of how managers like Gerry deal with customers. I doubt if i am the first one to encounter the lack of proffesionalism from Gerry, but for the sake of progress i thought i would bring it to pick n pay's attention. Maybe sending her for customer service training and educating her on the smart shopper service so that she can give tangible reasons, instead of walking away because she couldn't justify why i couldn't redeem my voucher.