WooCommerce Product sometimes resets to £0 in checkout.

Hi

I've looked into this everywhere and had success.

With WooCommerce, on one of my websites, when customers order products, occasionally the product will appear as no charge when they order it at checkout and essentially get the product for free. Even though the price etc is set when they first click order in the shop.

I've got little to no idea why it is doing this, any suggestions are hugely appreciated.

Many thanks.