The type "Microsoft.SqlServer.Types.SqlGeography" exists in both "Microsoft.SqlServer.Types.dll" and "Microsoft.SqlServer.Types.dll"

In my Windows class library (consumed by the MVC website) I installed NugetPackage Microsoft.SqlServer.Types (Spatial).

Now, using ado.net, I am trying to read the value by doing:

protected SqlGeography MapSqlGeography(DbDataReader reader, string key)
{
      return reader[key] is DBNull ? null : (SqlGeography)reader[key];
}

If I add a brake point in this line and in the window of the visual studio window, I type: "reader [key]", I can see the correct point (XXXX, XXX) like: " object {Microsoft.SqlServer.Types.SqlGeography}"

But, as soon as I try to throw, I have the following error:

(SqlGeography)reader[key]   The type 'Microsoft.SqlServer.Types.SqlGeography' exists in both
 'Microsoft.SqlServer.Types.dll' and 
 'Microsoft.SqlServer.Types.dll'

The main strange fact is that the dlls are exactly the same ...

As far as I know, I have only one "source" for this namespace / class name, it should not be duplicated ....

"":

using Microsoft.SqlServer.Types;
using System;
using System.Collections.Generic;
using System.Data.Common;
using System.Data.SqlClient;
using System.Threading.Tasks;

, ? .

# 1

NugetPackage `Microsoft.SqlServer.Types(Spatial) ' , : "Microsoft.SqlServer.Types(Unofficial)", /, "bin/obj", ....

... .

# 2

extern alias destination;

return reader[key] is DBNull 
        ? null 
        : (destination.Microsoft.SqlServer.Types.SqlGeography)reader[key];

:

Cannot cast 'reader[key]' (which has an actual type of 'Microsoft.SqlServer.Types.SqlGeography') 
to 
'Microsoft.SqlServer.Types.SqlGeography'
Microsoft.SqlServer.Types.SqlGeography