She refused to return my item and resell it to me!

I went to the store with my sister on Sunday the 27th and found the staff busy preparing stock for the sale that was to start the following day.There was a denim dungaree that l liked and it happened to be the last one and was my right size.l bought it with the intention to 'save' it n returned it the following day so l can benefit from the sale.I was assisted by Zakes who called Jane for authorisation.She was so rude and made me FEEL that she IS the store manager.She told me that she will return the item and keep it at the back so that l don't buy it back because it's against 'her' policy.She left me at the till with Zakes without finalizing my case.l also did NOT like her tone as well,and she did NOT treat me with respect and dignity.She MUST BE able to lead by example by communicating WELL with customers and make sure that l should come back for more and refer my friends and family to their store.l left the store with the item and will try to change it in one of their stores in Polokwane.The normal price was R380 and reduced to R250.