@HaiNN,The profile should show up in the UI. These events are created async so it may take some time before the event & profile show up in the UI.
A few things to check
1. are you receiving a 202 response from the API? If not, the output should provide more details about the error
2. are you using an email address that ends in “@example.com” or “@test.com”? These may be dropped by Klaviyo, since they’re not real email addresses.
3. It’s possible you’re using a profile ID and a conflicting identifier, as discussed in this post:
We need a few more details on what you’re currently doing and the behavior you’re seeing in order to help here.