The question is about the titles of the discounts I have within the flows, which say "INSERT-CODE". My question is whether the system will automatically create those discount codes, or if I need to enter them manually, or how should I set them up. What seems strange to me is that I don't know where to configure those discounts.
What methods are used to test these flows in real life?
Hi
Welcome to the Community!
This is a great question about using coupon codes in your Klaviyo email templates for flows. I see you have tagged Shopify here, so I hope it’s not too big of a leap for me to make to assume that is your current website platform 
The Klaviyo-Shopify integration allows you to create either Static or Dynamic coupon codes depending on your needs. Here are some quick differences between the two:
Unique, also called "dynamic," coupon codes are a random series of numbers or letters that a recipient can use one time. Each recipient will receive their own coupon code, and no two recipients will have the same code. Unique coupon codes are typically longer and more complicated than static codes.
Static coupon codes means that there's only one code (e.g., Welcome20). Every person will receive the same code and be able to use it on your site. Static codes are able to be shared out; however, they are easier to remember and use.
If you would like to use a Static discount code, I recommend creating this directly in your Shopify backend, and copy/paste the code you have generated into your email template.
For Dynamic discount codes, those can be configured in the Coupons tab in your Klaviyo account.
From there, you can follow this Help Center article for How to create unique coupon codes for Shopify After following the provided instructions on how to create your coupon code in Klaviyo, you can add the coupon tag in the text block shown in your screenshot using the following format:
{% coupon_code 'NAME_OF_YOUR_COUPON' %}
To test this, send a test email to yourself, and then navigate to your website, add qualifying item(s) to your cart, and apply the discount code at checkout to confirm all is in working order.
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Hope this helps!
-- Ashley Ismailovski
Hello, thank you very much for responding. How can I send reminders about the coupon expiration without repeating it or sending another one?
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