Disgusting customer service /none existant

Yesterday 22 December 2018 at 9 am my hubby and i bought 2pairs of sneakers for our daughters, so after paying an amount of R1,100.00.i personally informed the cashier named Petrus that i am going to fit the kids the shoes when i get home as i suspect 1 pair may have to be returned to which he responded "it is fine just note thet you can only exchange once mam" ok we left the shop i went home.fitted my kids the shoes and to my suspicion i had to return the size 7 puma sneaker. When i got back to the store around 1pm, i received the worst shock of my life as i was told my child's shoes cannot be exchanged because the shoe i fitted her is dirty?, i was put on the phone with the store owner or manager named Yolandie who told me i will not be assisted unless i bring back a clean shoe, to my response i asked her what musg i clean that shoe with? Should i use detergent and will she still accept the shoe if it has been washed? And if i had brought my daughter into the store and that shoe got dirty during fitting who would have paid for that shoe? And amazingly no one informed me of the terms and condition of exchange when i bought the shoes that i was supposed to use a sock to fit a shoe and it is their responsibility to communicate such info to their customers if they know of customer service, and she even had the guts to tell me after spending my money that she doesn't sell dirty shoes, i have never been so disrespected as a customer i have never been so maltreated. As we speak i sit here i returned from that godforsaken store with a small shoes size , my money is not back and my child needs to wear the shoe on christmas day. And sad part is as i am told i should have used a sock on my return , it was impossible to even use the damn sock because the shoe is too small . I hope i get assisted with this because i am willing to go all over social media with this.i am still angry and i regret ever going to tekkie town and i will tell everyone i know of this