selected value option All clear after display value How to prevent thi

Question

I work on asp.net mvc I face issue selected value All requests cleared after display result data and back to Pending Request

so my issue on selected value option if i select option All requests it display all requests success but drop down selected option display as Pending Request

so How to solve issue selected option clear after display data 

action GetSelectedDropDownChanged on controller WorkforceRequests hit and catched when make debug and detect value 1 if i select pending request and 2 if i select all request 

but issue when select option All request it back to option Pending Request so How to prevent this behaviour from happen

code details

<form action="/WorkforceRequests/GetSelectedDropDownChanged"  method="post">
    <select class="form-control" id="statusselect" name="statusselect">
        <option value="1">Pending Request</option>
        <option value="2">All requests </option>
    </select>
</form>

on controller WorkforceRequestsController

public async Task<ActionResult> GetSelectedDropDownChanged() //Assuming key in your dropdown is string
{
    string selectedValue = Request.Form["statusselect"].ToString();
    List<WorkforceRequest> workforceRequest = new List<WorkforceRequest>();
    if (selectedValue == "1")
    {                     
        workforceRequest = Workforce.GetPendingOnPalnningSection(RoleKey.PLS);
    }
    else
        workforceRequest = Workforce.GetAllRequestsOnPalnningSection(RoleKey.PLS);
    return View(workforceRequest);   
}