Partner Center REST API License to Subscription

Question

Hello,

we are working witht he Partner Center REST API to handle different use cases for our customers. We have a Problem to find the connection between a Customer Subscription and the SubscribedSku.

For example we want to do the following:

1. Remove a license from a user and update the amount of licenses from the corresponding subscription
2. Show all Licenses which are from a specifc subscription

We are working with REST Request and until now i cant find something in the Resources which helps me to find the way from a Subscription to a SubscribedSku/ProductSku.

Is this not possible or how could i solve these Problems.

Greetings form Germany.