How to make sure my .NET Core service running in EKS can find the https port?

I have created a .NET Core microservice using Microsoft sign-in as explained here. When running it locally or in a local Docker container, everything is working as expected. However, when running in EKS, I get a warning message in the logs:

Failed to determine the https port for redirect.

This warning is shown in this picture shown below which also shows that I also checked which port numbers are used (only 80 for http). I would be nice if netstat -tulp would show a port number for https because then I can just set it in the application settings (as explained by the Microsoft docs) ad resolve it directly.

The Microsoft docs clearly explain what to do when

The middleware logs the warning "Failed to determine the https portfor redirect."

but these do not make clear what to do if everything works fine in all environments except when running the application in EKS. Probably, I should do something in my EKS/Kubernetes configuration but I have no clue what to do.

Here is the service file:

Here is the warning message shown in the logs:

How do I resolve the warning message?