Hey @GabrielNoba , Sara from the Loox team here 
It sounds like on Klaviyo, you’re creating one discount code to use in a marketing campaign, instead of customer-specific unique codes. Since Loox generates a unique discount code for each customer, each one appears separately on your discount page.
However, if this is really important to you, you could change your Loox settings to create a single Shopify discount code instead of generating a one-time use code for each review. To achieve this, you can head into your Loox admin to Reviews > Collect Reviews > Discount for Photo/Video Reviews and select “Single Shopify Discount Code.” That being said, it’s important to note that there would be nothing to prevent customers from using this discount code multiple times, which is why we generally recommend selecting the other setting: “Auto-generate a one-time use code for each review.”
If you have any additional questions about this or anything else within our app, please don’t hesitate to reach out to our support team at the email below- we’d be more than happy to help!