Xamarin iOS app crashes on startup after updating to iOS 14.6

Hi, my app has a login and then a home page with donwloads lists from API.

After upgrading the iOS to 14.6 version it never starts. With earlier version it does.

And also I'm getting a warning that the Xamarin.ios is not found.

We upgraded everything up to date so we can compile with the latest versions.

Error: System.NullReferenceException
Mensaje = Object reference not set to an instance of an object

Method Main.cs On IOS package

using System;
using System.Collections.Generic;
using System.Linq;

using Foundation;
using UIKit;

namespace SOS.iOS
{
public class Application
{
// This is the main entry point of the application.
static void Main(string[] args)

    {
        // if you want to use a different Application Delegate class from "AppDelegate"
        // you can specify it here.
        UIApplication.Main(args, null, "AppDelegate");
    }
}

}

My stacktrace goes as follows:

• $exception {System.NullReferenceException: Object reference not set to an instance of an object
  at SOS.View.Landing.Home.LoadOrden () [0x00106] in <07085e5ebd574a3ebe24784d2332353a>:0
  at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__7_0 (System.Object state) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1021
  at Foundation.NSAsyncSynchronizationContextDispatcher.Apply () [0x00000] in /Users/builder/azdo/_work/1/s/xamarin-macios/src/Foundation/NSAction.cs:178
  at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)
  at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Users/builder/azdo/_work/1/s/xamarin-macios/src/UIKit/UIApplication.cs:86
  at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0000e] in /Users/builder/azdo/_work/1/s/xamarin-macios/src/UIKit/UIApplication.cs:65
  at SOS.iOS.Application.Main (System.String[] args) [0x00001] in C:\Users\hugog\source\repos\PhilipsSOSApp_08062021\SOS\SOS.iOS\Main.cs:17 } System.NullReferenceException
• base {System.SystemException} System.SystemException
• base {System.Exception} System.Exception
• Data {System.Collections.ListDictionaryInternal} System.Collections.ListDictionaryInternal
  Count 0 int
  IsFixedSize false bool
  IsReadOnly false bool
  IsSynchronized false bool
• Keys {System.Collections.ListDictionaryInternal.NodeKeyValueCollection} System.Collections.ListDictionaryInternal.NodeKeyValueCollection
  Count 0 int
  IsSynchronized false bool
• SyncRoot {object} object
• Non-public members
• IEnumerator
  SyncRoot {object} object
• Values {System.Collections.ListDictionaryInternal.NodeKeyValueCollection} System.Collections.ListDictionaryInternal.NodeKeyValueCollection
  Count 0 int
  IsSynchronized false bool
• SyncRoot {object} object
• Non-public members
• IEnumerator
• Non-public members
• IEnumerator
  HResult -2147467261 int
  InnerException (null) System.Exception
  Message "Object reference not set to an instance of an object" string
  Source "mscorlib" string
  StackTrace " at SOS.View.Landing.Home.LoadOrden () [0x00106] in <07085e5ebd574a3ebe24784d2332353a>:0 \n at Syst…" string
• Static members
• Non-public members
  _COMPlusExceptionCode -532462766 int
• s_EDILock {object} object
• Non-public members
  _HResult -2147467261 int
  _className "System.NullReferenceException" string
• _data {System.Collections.ListDictionaryInternal} System.Collections.ListDictionaryInternal
  _dynamicMethods (null) object
  _helpURL (null) string
  _innerException (null) System.Exception
  _message "Object reference not set to an instance of an object" string
  _remoteStackIndex 0 int
  _remoteStackTraceString (null) string
• _safeSerializationManager {System.Runtime.Serialization.SafeSerializationManager} System.Runtime.Serialization.SafeSerializationManager
  _source "mscorlib" string
• _stackTrace {System.IntPtr[21]} System.IntPtr[]
  _stackTraceString (null) string
• captured_traces {System.Diagnostics.StackTrace[1]} System.Diagnostics.StackTrace[]
  caught_in_unmanaged 0 int
  native_trace_ips (null) System.IntPtr[]

Advertencia Debugging symbol file for '/Users/MezcalTeam/Library/Caches/Xamarin/mtbs/builds/SOS.iOS/cae444b42975878605001bc50213d52b2b0d52fb4a5adc92030be99e420cbf67/obj/iPhone/Debug/device-builds/iphone10.6-14.6/mtouch-cache/1-Link/Xamarin.Forms.Core.dll' does not match the assembly and is ignored. SOS.iOS

Advertencia MSB3245 No se pudo resolver esta referencia. No se encuentra el ensamblado "Xamarin.iOS". Compruebe si el ensamblado existe en el disco. Si el código necesita esta referencia, podrían producirse errores de compilación. SOS C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\MSBuild\Current\Bin\Microsoft.Common.CurrentVersion.targets 2202

Gravedad Código Descripción Proyecto Archivo Línea Estado suprimido
Advertencia Xamarin.Forms recommends TargetPlatformVersion >= 10.0.17763.0 (current project is -1) SOS C:\Users\hugog.nuget\packages\xamarin.forms\4.6.0.726\buildTransitive\Xamarin.Forms.targets 233