Appilix push notification

[web-works]

We have a local news website running als with an (android) app. Until now we have te login to appilix to send notifications to app users whenever a new article is published.
Appilix als has an API. I tried to get it running from a separate form after publishing an article. The form will send without any errors, but notifications do not arrive.
It should be like this (from appilix)

curl -X POST https://appilix.com/api/push-notification 
-d 'app_key=the key' 
-d 'api_key=the other key' 
-d 'notification_title=titel' 
-d 'notification_body=tekst'

This is how the api is setup

Can anyone point me in the right direction to get this working?

[Teodor]

You're wrongly sending the app_key and api_key as headers, while they should be under Input Data, according to the code you posted.

[web-works]

Thanks for the quick reply. Changed, but still no notification coming in.

However, when I click on Define Api Schema > Fetch Schema, notification is being sent, but it does not have any content. And, of course, this is not the intention of it. It should send when form button Send Notification is clicked.