Double opt-in confirmation links return NXDOMAIN in Estonia

Hi,

I use Klaviyo’s free plan with double opt-in. A customer reported that the confirmation link would not open. I reproduced the issue on two internet connections in Estonia: Elisa and Telia.

The affected hostname is manage.kmail-lists.com. Chrome displays DNS_PROBE_FINISHED_NXDOMAIN.

DNS tests from one affected connection:

• Default DNS via the router: NXDOMAIN.

• Google DNS (8.8.8.8): resolves successfully.

• Cloudflare DNS (1.1.1.1): resolves successfully.

Both public resolvers return the CNAME manage.kmail-lists.com.cdn.cloudflare.net and IP addresses 172.64.146.244 and 104.18.41.12.

The confirmation link works on mobile data. Switching Chrome’s Secure DNS provider to Google also made it open successfully.

Customers affected by this issue cannot complete their subscription, leaving their profiles as “Never subscribed”.

Separately, confirmation emails took approximately 5–10 minutes to arrive in my latest test, and over 10 minutes in an earlier test.

Could a Klaviyo team member escalate this to the technical team to investigate the DNS issue and advise how to investigate the email delays? I’m on the free plan and cannot open a regular support ticket.

Thank you.