Zara Horrible Shopping Experience

I bought a medium sized jacket from Zara Menlyn with a price tag of R1699,99. Upon paying, the cashier ringed the jacket to be R1299,99 and that is what I paid. My cellphone number was taken for a receipt but I did not receive any receipt still. Unfortunately, the jacket was too small for my partner. I called the store and they advised that my number and receipt would be picked up from any Zara system if punched in. We attempted to exchange at Mall of Africa and was given a hard time without a receipt. Menlyn said we could come to their store for an up size. Upon going to Menlyn for an upsize, we were told that we will need to pay R1000 more as the price was incorrect. I argued to say I am willing to pay R1699,99 which was on the price tag (Mall of Africa removed it but luckily, I had taken a picture of the tag). We were advised log a query with customer service. However, customer service cannot assist us without a receipt which Menlyn is refusing to share. No one is willing to assist us. We are made to take the fault of the store.