Hey @MuscleP - is this problem still happening for you?
A few things I found whenever I see weird glitches on Klaviyo. Make sure you’re logged into the right Klaviyo Account, especially if you’re switching between different Klaviyo Accounts, sometimes you get an error like this if you had this in a separate tab and forgot you switched accounts.
Or, if you’re like me, I have my Tab opened for a very long time (like for a few days) and came back to it - a re-login to refresh the session helps.
Secondly, in very rare occasions, there might be some issues on Klaviyo’s side. You can always check Klaviyo’s Status page where they’re very transparent about any known issues that might cause some glitches. You can check the status on their Status Page (or better yet, Subscribe to Updates) here:
https://status.klaviyo.com/
Hope this helps next time you run into it!