Sending emails via API doesn't work correctly

Hello, I am trying to send email according to the docs:
Using this body:

"user_id": "1",
"subject":"Something is wrong",

I am getting response 202 which signals that everything is fine. I can also see the email in the UI but only on dashboard in recent activity or in the contact’s chronological view the email was sent to. But it’s not clickable, I see the subject and that it was sent but I cannot open it. In group view there’s nothing. When I send an email from the UI it works just fine. The email from the API won’t also show up in history (Reports → Sent Emails Tracker). The one from the UI shows there. Could someone help me with it?

If you dont mind submitting a ticket on this I am happy to investigate why the endpoint may not be providing an accurate response.

However, it looks like the the payload should have “contacts” rather than “contact_ids”. Also it should be a list(array) of longs rather than a single string.

"contacts": [
"user_id": 1,

I think you should also add the contacts Ids inside of an array and not as a string, even if you send the email to only one contact.