C# RLNET/OPENTK System.MissingMethodException during run-time

I am trying to make a small 2d game in c# using the RLNET library. The RLNET library has OpenTK as a dependency, so I added the latest versions of both RLNET and OpenTK to my project using the NuGet packages manager in Visual Studio. I was following along with a tutorial explaining how to work with these libraries. But, when I got to running the code I ran into a MissingMethodException at run-time.

The tutorial I was following along with is here: https://roguesharp.wordpress.com/2016/03/02/roguesharp-v3-tutorial-creating-the-project/

The Solution Explorer shows both libraries included in the project under the References dropdown. And I also included them in my code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using RLNET;
using OpenTK;

namespace Rouge_Game
{
    class Program
    {
        private static readonly int _screenWidth = 100;
        private static readonly int _screenHeight = 70;

        private static RLRootConsole _rootConsole;

        static void Main(string[] args)
        {
            // This must be the exact name of the bitmap font file we are using or it will error.
            string fontFileName = "terminal8x8.png";
            // The title will appear at the top of the console window
            string consoleTitle = "RougeSharp V3 Tutorial - Level 1";
            // Tell RLNet to use the bitmap font that we specified and that each tile is 8 x 8 pixels
            _rootConsole = new RLRootConsole(fontFileName, _screenWidth, _screenHeight,
          8, 8, 1f, consoleTitle);
            // Set up a handler for RLNET's Update event
            _rootConsole.Update += OnRootConsoleUpdate;
            // Set up a handler for RLNET's Render event
            _rootConsole.Render += OnRootConsoleRender;
            // Begin RLNET's game loop
            _rootConsole.Run();
        }

        // Event handler for RLNET's Update event
        private static void OnRootConsoleUpdate(object sender, UpdateEventArgs e)
        {
            _rootConsole.Print(10, 10, "It worked!", RLColor.White);
        }

        // Event handler for RLNET's Render event
        private static void OnRootConsoleRender(object sender, UpdateEventArgs e)
        {
            // Tell RLNET to draw the console that we set
            _rootConsole.Draw();
        }
    }
}

The part of the code that has a run time error is this:

    // Event handler for RLNET's Render event
        private static void OnRootConsoleRender(object sender, UpdateEventArgs e)
        {
            // Tell RLNET to draw the console that we set
            _rootConsole.Draw();
        }

When I run the project it compiles with no errors and the program launches, but then throws this exception:

System.MissingMethodException
  HResult=0x80131513
  Message=Method not found: 'Void 
OpenTK.Graphics.OpenGL.GL.BlendFunc(OpenTK.Graphics.OpenGL.BlendingFactorSrc, OpenTK.Graphics.OpenGL.BlendingFactorDest)'.
  Source=RLNET
  StackTrace:
   at RLNET.RLRootConsole.Draw()
   at Rouge_Game.Program.OnRootConsoleRender(Object sender, UpdateEventArgs e) in C:\Users\pjmul\source\repos\Rouge Game\Rouge Game\Program.cs:line 45
   at RLNET.RLRootConsole.window_RenderFrame(Object sender, FrameEventArgs e)
   at System.EventHandler`1.Invoke(Object sender, TEventArgs e)
   at OpenTK.GameWindow.OnRenderFrame(FrameEventArgs e)
   at OpenTK.GameWindow.RaiseRenderFrame(Double elapsed, Double& timestamp)
   at OpenTK.GameWindow.DispatchRenderFrame()
   at OpenTK.GameWindow.Run(Double updates_per_second, Double frames_per_second)
   at OpenTK.GameWindow.Run(Double updateRate)
   at RLNET.RLRootConsole.Run(Double fps)
   at Rouge_Game.Program.Main(String[] args) in 
C:\Users\pjmul\source\repos\Rouge Game\Rouge Game\Program.cs:line 32

I don't understand this error however as when I use the object viewer built into Visual Studio I can find the "missing" function when I open OpenTK.dll. Any suggestions as to how I might fix this error are greatly appreciated. I would also like to thank anyone who takes the time to help me in advance.

There is something wrong with the 3.x branch of OpenTK. Try downgrading your OpenTK package back to 2.x and it will work.