My name is Lilith, I'm on the Social Care team at Shopify.
If you've used the Discounts guide and you're encountering this message at checkout, there could be a few different factors that can cause this error. It could be a setting in the discount, time and date, customer actions and details at checkout, or other reasons.
I'd like to take a closer look at this if you'd like. I will have to send over an email to you to get you authenticated. Would you like me to check into this for you?
Let me know how you do with the information above! I'm happy to answer any questions you think of as you work on your business.
HI, @Marugalvis. If you've taken a look at the guide in the solution here and you're not sure where the parameter might be missing in your discount setting you can certainly reach out to our live support team so they can have a look at the discount settings and help you out.
They’ll need to access your account in order to resolve this issue. While we’re not able to provide account-specific support via the public forum in Shopify Community at this time, we’d be happy to continue assisting you through live chat, email, or callback. Please visit https://bit.ly/3cJkx8V and log in to your account to create a support request.