The documentation at https://github.com/Azure-Samples/service-fabric-java-quickstart
says:
Party clusters are free, limited-time Service Fabric clusters hosted on Azure. They are run by the Service Fabric team where anyone can deploy applications and learn about the platform. To get access to a Party Cluster, follow the instructions.
See Discontinuing Party Clusters
https://techcommunity.microsoft.com/t5/azure-service-fabric/discontinuing-party-clusters/ba-p/792040