Cart Pre-loaded with 1 Product

[Tryer]

VM 4.0.22
Joomla 4.3.3
PHP 7.4.33

When loading the VM cart, it is pre-loaded with 1 product - with a warning message that "Your previously stored cart content has been loaded". I can delete the product in the normal way and proceed with shopping. However, after leaving VM to browse elsewhere on the site, then returning to the shop, the cart is again pre-loaded with the same product.
Any assistance would be appreciated.

[jenkinhill]

The cart should not be cached, check that the System - Page Cache plugin is not activated.