How to consume Personalized Recommendation endpoint in deployed ui5 app

Hello experts,

I am trying to consume the next-items endpoint of the Personalized Recommendation Service within my HTML5 Application, which is deployed in SAP BTP Cloud Foundry.

Locally I used a proxy to consume the endpoint and that's working well.

But it is not working in the deployed version:

First I created a destination in the BTP:

Full Token Service Url: https://<...>.authentication.eu10.hana.ondemand.com/oauth/token

In my xs-app.json of the ui5 app I configured the destination:

And in my controller I made an AJAX POST request to following URL: "/standard/rs/vs/tenants/{myTenant}/recommendations/next-items?site={mySite}"

In my HTML5 Application and when I open the app in the Launchpad Service I get an 403 Forbidden Response

Can anyone help me with this problem?

Thank you.

Matthias