Hi @Satu_J 

there could be many reasons for this eg could be in spam. Could it be that your client was sent an email less than 24 hours ago and that smart sending is on ( preventing that same profile receiving another email within 24 hours)

I would recommend that you take a look at this course on Deliverability 

https://academy.klaviyo.com/path/deliverability-certificate?utm_source=community&utm_medium=cross_promo&utm_campaign=deliv_cert_launch

@Satu_J

There is chance that the email landed either in Promotions or even worse in Spam folder. This usually happens if the account has bad health (meaning if it has really bad open rate on the previous campaigns (under 10%) or even bad click rate or bounce rate, unsubscribe and so on.

The deliverability course suggested in the previous course is great resource if you have time to watch. If not I would suggest at least looking into this article which may help clear some things up: https://help.klaviyo.com/hc/en-us/articles/115000201131-Understanding-and-monitoring-email-deliverability-performance

Thank you for the responses, I appreciate the help! The client said that they or their family members who are subscribed did not see the email in spam, or any other folders either. This was the first email that was sent from this Klaviyo account so there’s not much history to compare this to...

I’ll make sure to check out the training resources!