Why does my shopping cart show as empty when customers add items?

When customers try to view there cart with items in it and hit cart it shows nothing cart is empty and they can not proceed to checkout

Hi, this looks to be a very curious issue. Could you share a link to your store so I can help you to check please?

Hi Thanks for the reply been so busy!The link to Kingsmans Collections website https://kingsmancollection.com.au

The problem is when costumers try to order stuff and then they go to the shopping cart the shoping cart is blank so they cart checkout. Costumers keep texting me on shopify inbox saying its not working and the shoping carts blank.
Thanks Leyette