Pure Gold Jewellers review: I purchased a wristlet, its weight is 6 gm only, but its value was calculated on 12.5 gm

On 9th Oct'23 I purchased a wristlet in Abu Dhabi International airport from Pure Gold Company. The salesman told me that its weight is 12.5 gm and the price told by him seemed ok to me and I paid 3299 Dirham by my debit cards from India. I was a wheelchair passenger and I purchased at around 7-15 pm whereas my flight was at 9 pm. So I did not check weight in a hurry. Moreover I have faith on all gold shops in UAE. That time I was not given invoice, the salesman asked my email id and told me that it will be sent by email. Next day as I received invoice I noticed that weight of wristlet is only 6 gm instead of 2.5 gm. I went to a famous jewellery shop in Kolkata and I found weight is only 6 gm. I wrote to your customer care to give break up of price of gold, making charge and VAT if any in 3299 Dirham, but they are repeatedly saying that it is unique piece, its value is 3299 Dirham. The salesman told me that MC is 25% of gold price. So he charged me on 12.5 gm gold instead of 6 gm gold. I want the extra money back immediately. Otherwise I'll complain to appropriate authority in UAE.