Cannot access any service in Helm deployment

[tegebe]

Hello,

I deployed Activiti 8.1 via Helm.
Output is as follows:

-              _   _       _ _   _    _____ _                 _
     /\       | | (_)     (_) | (_)  / ____| |               | |
    /  \   ___| |_ ___   ___| |_ _  | |    | | ___  _   _  __| |
   / /\ \ / __| __| \ \ / / | __| | | |    | |/ _ \| | | |/ _` |
  / ____ \ (__| |_| |\ V /| | |_| | | |____| | (_) | |_| | (_| |
 /_/    \_\___|\__|_| \_/ |_|\__|_|  \_____|_|\___/ \__,_|\__,_|
 Version: 8.1.0

Thank you for installing activiti-cloud-full-example-8.1.0

Your release is named activiti.

To learn more about the release, try:

  $ helm status activiti
  $ helm get activiti

Get the application URLs:

Activiti Gateway         : https://activiti.k8s.example.com
Activiti Identity        : https://keycloak.k8s.example.com/auth

Activiti Runtime Bundle  : https://activiti.k8s.example.com/rb
Activiti Cloud Connector : https://activiti.k8s.example.com/example-cloud-connector
Activiti Query           : https://activiti.k8s.example.com/query
Activiti Audit           : https://activiti.k8s.example.com/audit
Notifications GraphiQL   : https://activiti.k8s.example.com/notifications/graphiql
Notifications WebSockets : https://activiti.k8s.example.com/notifications/ws/graphql
Notifications Graphql    : https://activiti.k8s.example.com/notifications/graphql

I'm using ingress-nginx/ingress-nginx.
Btw. Helm is printing out it's https:// but actually it is http://

When calling http://activiti.k8s.example.com/ I get a HTTP 404.
When calling 'http://keycloak.k8s.example.com/auth' I get the Keycloak interface. -> OK
When calling 'http://keycloak.k8s.example.com/modeling-service' (or any other service) I get the following output in browser:

{
  "links" : [ {
    "rel" : "profile",
    "href" : "http://activiti.k8s.example.com/rb/profile"
  } ]
}

Any ideas or clues?

Thank you in advance!