Hey @Masha M! 

Welcome to the Community =)

"Catalog Item Unavailable" typically means that one or more of the email addresses you are trying to send to are no longer valid, or that they have unsubscribed from your emails.

To fix the issue, you can try the following:

1. Verify the email addresses: Check the email addresses in question to make sure that they are typed correctly. Also, verify that the email addresses are still active and in use.
2. Check the unsubscribe list: See if the email addresses in question are on your unsubscribe list. If they are, you will not be able to send emails to them.
3. Check your email deliverability: Make sure that your domain is not blacklisted and that your sending IP address has a good reputation. You can use online tools to check your domain and IP address against blacklists.
4. Resend the email: If the email addresses are valid, you can try resending the email to them after a few days. Sometimes, email providers may temporarily block or mark emails as spam, and resending the email can resolve the issue.

If the issue persists, you may want to reach out to Klaviyo support for further assistance. They will be able to provide more specific guidance based on your particular setup and any errors that you may be encountering.

Thank you!
Letters arrive at the email address when it matches the action configured in the flow, but does not go to the same address configured in the company.

Hi @Masha M! You're welcome) 
This is more difficult (but I will try to help you in any way I can).
 

It is possible that the email address in your flow and campaign settings are different, causing the emails to be sent to different addresses. To resolve this issue, please check the email address configuration in both your flow and campaign settings to make sure they are the same.

Another possible issue is that the email address you have set up in your Klaviyo account might not be properly verified. You can check your verified email addresses in the account settings and make sure the email address you are using for your campaigns is properly verified.

If the issue persists, it might also be a good idea to check your email client's spam folder.

If this does not solve the problem then you need to contact support, it may be a bug klaviyo and this will solve their engineers.