Compiling error when working on a package set as a separate assembly

Hi, 

I'm trying to compile the code below from a package set as a a separate assembly but I'm getting the error attached even though the object mentioned on the error is part of the package. 

What am I missing?

Thanks,

Jose

Error:

Object exists on package

Code generating the error:

using System;

using System.Collections.Generic;

using System.Linq;

using Terrasoft.Core;

using Terrasoft.Core.Entities;

using Terrasoft.Configuration;    

public class UsrPPDRCorrespondenceHelper

{

    private UserConnection UserConnection { get; }

    

    public UsrPPDRCorrespondenceHelper(UserConnection userConnection) {

        UserConnection = userConnection;

    }

    

    public Guid GetStatus(Guid corrId) {        

        var esq = new EntitySchemaQuery(UserConnection.EntitySchemaManager, "UsrPPDRCorrespondence");

        esq.AddAllSchemaColumns();

        Entity queryResult = esq.GetEntity(UserConnection, corrId);

        if (!(queryResult is UsrPPDRCorrespondence corr)) {

            throw new Exception($"Unable to get Correspondence status for ID {corrId}");

        }

        if (corr.UsrStatus == null) {

            throw new Exception($"Correspondence status for ID {corrId} is empty");

        }

        return corr.UsrStatus.Id;

    }

 }