Visual Studio Code – In my C# project I had to downgrade a nuget package to an older version. But I still get get Error reg. uninstalled newer version package why?

In my C# project (VS 2022) I had to downgrade a nugget package (OPCLabs.EasyOPC) to an older version due to some functional problems on the new version. Therefore I have uninstalled the nugget package (V5.71) and installed the older version (V5.62).

I can also confirm from the packages under the project tree that 5.62 is installed, and 5.71 is not existing anymore.

After clean and rebuild the project without any Errors, I get when I use a function of the library the Error:
"The system cannot find the file specified.File name: ‘OpcLabs.EasyOpcClassicCore, Version=5.71.401.1, Culture=neutral, PublicKeyToken=6faddca41dacb409’ "

So it is looking for a file of the version that I have uninstalled. I think this is more a problem of Visual Studio 2022 , then a problem of the library, because I could work with the older version without problem in the past.

What can I do? Do I have to remove some rest files manualy?

My Code: (I get the Error as soon as my function is called)

    using OpcLabs.EasyOpc;
    using OpcLabs.EasyOpc.DataAccess;
    using OpcLabs.EasyOpc.OperationModel;

    private async Task Browse_OPC_Servers()
    {
        var client = new EasyDAClient();
        client.InstanceParameters.EnableNetApiClient = false;
        ServerElementCollection serverElements;
        try
        {                
            serverElements = client.BrowseServers("10.92.XXX.XXX");
        }
        catch (OpcException opcException)
        {
            Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
            Console.ReadLine();
            return;
        }

        foreach (ServerElement serverElement in serverElements)
        {
            Console.WriteLine($"ServerElements("{serverElement.ClsidString}").ProgId: {serverElement.ProgId}");                
            
        }
        Console.ReadLine();
    }