I removed the web in my list but still it show the output

I tried to show and hide the section base on checkbox list. At First I received the value from back end Web and Mobile. I removed the Web in checkbox list and make it as a desktop. Now received 3(desktop, mobile, web) values instead of 2(Desktop, Mobile) values

 string displyOption = string.Empty;
    if (Model.SliderDisplay != null)
    {
        List<string> list = new List<string>();
        var SliderDisplay = Model.SliderDisplay;



        list.AddRange(Model.SliderDisplay);
        if (list.Count() == 0)
        {
            displyOption = "NoneShowClass";
        }
        else if (list.Count() > 1)
        {
            displyOption = "";
        }
        else
        {
            displyOption = !string.IsNullOrEmpty(list[0]) ? list[0] + "ShowClass" : "";
            if (string.IsNullOrEmpty(displyOption))
            {
                displyOption = "NoneShowClass";
            }
        }
    }