If you have multiple carts in your website with different payment options, you can prevent customers from adding products from a second cart.
A typical scenario is where you have a second cart for Subscriptions with a recurring payment option you do not want to be available other orders.
To prevent ordering from other carts
- Navigate to the current shopping cart page, and choose the CHECKOUT OPTIONS button from the Display Options section.
- Check the option 'Prevent Purchases Between Different Shopping Pages' checkbox from the sidebar options in the Checkout options section.