Baby City horrible customer service and refuse to exchange!!!

Very bad experience with Baby city at Mall@55 in Centurion. From the security lady at the door to the manager they are all soo *********** with poor customer service!!! I explained to them how my husband bought the huggies Gold twin packs *3 and they were all number 3 the 6 jumbo packs abt 2 months ago.. Now the baby has grown and they are tight on her.. The packaging is still in perfect condition as the store.. Even the price tag belongs to them coz we always bug nappies there but they refused to exchange for me to get a size 4.. Who keeps till slips from over 2 months ago?? Was there ever looting and Centurion?? What does that have to do with me coz I've previously exchanged an item or 2 there hustle free now this?? What a waste of our money.. A whole R400.. I will never buy from that shop again shame.. Besides the fact that they refused to exchange the bad service and securities with attitude are sooo uncalled for!!! I will make sure none of my family and friends ever buy there again.. Pity coz we loved the shop and always spend over R1000+ when we do go to buy in bulk.. Im very dissapointed and annoyed to say the least!! What must I do with 2 jumbo pack nappies that doesn't fit my baby?? Pathetic if u ask me..