Hey @duyen1616! Welcome to the Klaviyo Community!

Here are the methods to fix your problem, so you can get back on track quickly.

1. Check Segment & Settings: Analyze emails bouncing for "Invalid Address" and confirm your default Klaviyo "From" address is correct (double-check for typos!).

2. Clean Up Your List: Remove inactive/invalid addresses. Klaviyo suppresses hard bounces, but consider a list cleaning tool for a deeper scrub.

3. Authentication Matters: Implement email authentication (SPF, DKIM, DMARC) to improve deliverability and avoid spam flags.

4. Klaviyo Support: If you are still stuck contact Klaviyo support with details about the bounce rate and your troubleshooting efforts.

Remember, a clean list, proper authentication, and a watchful eye on bounce rates will keep your Klaviyo sends reaching the right inboxes!

Hi @Sujal, thanks for your advice. It's been unusual the last several days. The default Klaviyo "From" address is completely correct. I will try to clean up the list and follow up further.

Sure! Let me know how it goes!

Hi @Sujal  
I noticed that our email was sent through shared.klaviyomail.com. I checked and found an NS verification error. Now we have it back in sync. I hope everything is good. Thank you.

Sweet! Glad to be of help!