Bonaero Park Pick n Pay Worst Store

I bought a microwave oven from your Mall of Africa store and it was not a good product. Upon purchase I asked if there were any issues could I returned it and was told that won't be a issue and it could be returned at any of the stores. It been a week and today I went into the pick n pay store which is closest to me Bonaero park and was told NO. Something about a family store and corporate store. I am very disappointed with the service received!