Entity Framework 6.0 - Evaluation of method System.Linq.Queryable.Whewre() requires use of the static field - entity-framework

Question

I am using Entity Framework 6.0 with .NET framework 4.5 inside a SharePoint 2013 project, to get data from a view in a database based on a specific condition.
My Context.cs file looks like this:
namespace Clients
{
using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
public partial class Clients_ReqsEntities : DbContext
{
public Clients_ReqsEntities()
: base("name=Clients_ReqsEntities")
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
throw new UnintentionalCodeFirstException();
}
public virtual DbSet<ClientInfo> ClientInfo { get; set; }
}
}
And my ClientInfo.cs file looks like this:
namespace Clients
{
using System;
using System.Collections.Generic;
public partial class ClientInfo
{
public string ClientTitle { get; set; }
public string ClientID { get; set; }
public string ClientUNumber { get; set; }
}
}
I am trying to get data from this view based on the ClientUNumber, using this query:
string anyValue = "something";
var client = (context.ClientInfo.Where(c => c.ClientUNumber.Trim() == anyValue)).FirstOrDefault();
The returned value is always "null", however if I run that line of code in Watch window, I am getting this error:
Evaluation of method System.Linq.Queryable.Where() requires use of the static field System.Data.Entity.Core.Objects.ObjectQuery`1[Clients.ClientInfo].MergeAsMethod, which is not available in this context.
I tried using this query too:
(from c in context.ClientInfo where c.ClientUNumber.Trim() == anyValue select c).FirstOrDefault();
But I am getting the same error.
Some posts suggest to use ToList(), but this will get all records from the DB, and I keep getting Evaluation Timedout. So I don't think this is the right approach. PS: the view has 7k records.
Any help is appreciated.