KeyNotFoundException in GraphQL .net Entity Framework

I am using below with two DbContexts:

https://github.com/SimonCropp/GraphQL.EntityFramework

I get this error:

GraphQL.ExecutionError: Error trying to resolve project.

System.Collections.Generic.KeyNotFoundException: The given key 'Models.Master.Project' was not present in the dictionary.

at System.Collections.Generic.Dictionary2.get_Item(TKey key)
at IncludeAppender.AddIncludes[TItem,TSource](IQueryable1 query, ResolveFieldContext1 context) in C:\\projects\\graphql-entityframework\\src\\GraphQL.EntityFramework\\IncludeAppender.cs:line 20
at GraphQL.EntityFramework.EfGraphQLService.<>c__DisplayClass21_02.<b__0>d.MoveNext() in C:\projects\graphql-entityframework\src\GraphQL.EntityFramework\EfGraphQLService_Queryable.cs:line 80

End of stack trace from previous location where exception was thrown

at GraphQL.Instrumentation.MiddlewareResolver.Resolve(ResolveFieldContext context)
at GraphQL.Execution.ExecutionStrategy.ExecuteNodeAsync(ExecutionContext context, ExecutionNode node)

End of inner exception stack trace

When I try to add two models of two DbContexts as following in startup.cs (in following, if I remove second line, then it works perfectly. But that I need for my second DbContext).

EfGraphQLConventions.RegisterInContainer(services, ProjectDataContextBuilder.ProjectModel); //This is creating issue as of now. wasn't issue when checked with my and your.
EfGraphQLConventions.RegisterInContainer(services, MasterDataContextBuilder.MasterModel);

DataContextBuilder classes are as follows:

static class MasterDataContextBuilder
{
    static MasterDataContextBuilder()
    {
        using (var masterDataContext = InMemoryContextBuilder.Build<ecdiscoMasterContext>())
        {
            MasterModel = masterDataContext.Model;
        }
    }

    public static IModel MasterModel;
}

static class ProjectDataContextBuilder
{
    static ProjectDataContextBuilder()
    {
        using (var projectDataContext = InMemoryContextBuilder.Build<ecdiscoProjectContext>())
        {
            ProjectModel = projectDataContext.Model;
        }
    }

    public static IModel ProjectModel;
}

Note: In error. Project is model of MasterDbContext.

Another DbContext is Project. which is separate per tenant. So that is ProjectDbContext (which doesn't have Project model).