Money deducted and vanished

I am hosting a 75 year old guest from London who bought sneakers on Saturday, 18/2/23 from Fabiani at Fourways Mall Johannesburg. This purchase on Saturday was his third purchase in just 2 days from 3 different branches. We found ourselves at Fourways because he just loved this pair of sneakers we saw at Cresta and Clearwaters mall but did not have his size. We were then referred Fourways Mall for this shoes. After swiping his card at Fourways Mall for this sneaker, R2,299.00 was deducted from his account but because the receipt said declined, we were told due to a system error, he had to leave the store without a refund or sneakers. Since Monday, 20/2/23, we have called branch, call centre, Cape Town, Durban and Fourways on several occasions, submitted everything they asked every time we call, reached out to the CEO, Anthony on FB and Linked and even asked the Fabiani page to assist. We have confirmed with my guests London bank that this money was taken and not refunded, we even provided Fabian's Fourways Branch the ARN code and since then, I sent 5 emails and STILL no response. I am not sure how much longer this has to take but from where I stand, Fabiani has an unallocated R2,299.00 hanging on their system and refusing to give it back. Our house guest is very upset and goes home tomorrow. Can someone urgently get back to me???