No Proof of Refund for Returned Goods (4 months and waiting)

In October 2018 I ordered a pair of shoes through the New Balance website, after having visited a store to confirm the sizing, which had to be returned due to a sizing error (the shoes were cheaper on the website). I subsequently went to the New Balance store in Menlyn to buy the same pair of shoes from the store, in the correct size so as to avoid another sizing error, but at a higher price. I have been waiting since October for New Balance to provide proof/confirmation that the initial amount paid for the internet order has been refunded to me. Everytime I submited a query (10/10/2018, 14/12/2018, 12/12/2018, ), I am told that the finance office is closed or that the finance department will revert. Nothing. This is rather poor for such a big brand. I was also concerned that when New Balance arranged for the collection of the pair of shoes that needed to be returned, the courier did not require me to sign that I had in fact handed him the shoes; I did, however, jot down the courier vehicle's registration number.