If you're using Cloudshelf in your store you'll need to ensure that your prices on your website are updated regularly so they are displaying the correct pricing.
You'll also need to make sure that your product information such as; stock, images, sizing availability etc are also being updated regularly on your Shopify store. This will make your Cloudshelf much more effective and will give your customers the relevant information when they're browsing and purchasing your products through Cloudshelf.
When you log on to your Shopify store and select Products > All products - Here you will see how you can manage all of your products and amend pricing, stock, sizing etc.
Anything that you update on your Shopify site will automatically reflect on your Cloudshelf within a few minutes of you making the change.