Unmapped registration logs in Spring Netflix DGS

I am currently working on the Spring Boot with Netflix DGS for Apollo Federated system. I am encountering issue logs like this, which I have mentioned below. Can someone clearly explain what this error means and how to fix it? I am actually new to this.

Thanks in advance!

Unmapped fields: [Query._service, Query._entities]
Unmapped registrations: {Query._entities.Product=com.netflix.graphql.dgs.springgraphql.DgsGraphQLSourceBuilder$DgsSelfDescribingDataFetcher@294c44b7}
Unmapped arguments:
Skipped types: