remote attribute does not allow to post - asp.net-mvc

Question

I'm trying to check if TerminalID already is taken by another model. The Ajax is posting back correctly and error message also can be seen, but the page will not allow me to submit , I only need to check this information while input to display error message and then post anyway . help me please
Model :
public class MoveModel
{
[Required]
[Remote("CheckExistTrm", "MoveModel")]
public int TerminalID { get; set; }
public string User { get; set; }
........
}
Controller:
public JsonResult CheckExistTrm(int TerminalID)
{
var terminal = db.Terminals.Find(TerminalID);
if (terminal == null)
return null;
var agrdet = (from t in db.AgreementDetails where (t.TerminalID == terminal.TerminalID && t.Condition == "New") select t).FirstOrDefault();
if (agrdet != null)
{
var agreement = db.Agreements.Find(agrdet.AgreementID);
return Json("consider! this terminal is active in the agreement: " + agreement.AgreementNumber ,JsonRequestBehavior.AllowGet);
}
else
{
return Json(true, JsonRequestBehavior.AllowGet);
}
}
View (I am using devexpress ):
#using (Html.BeginForm("CreateAndEdit", "MoveModel", FormMethod.Post, new { #class = "edit_form" })){
#Html.AntiForgeryToken()
#Html.Hidden("MoveModelID")
<div class="line">
#Html.DevExpress().Label(
settings =>
{
settings.ControlStyle.CssClass = "label";
settings.AssociatedControlName = "TerminalID";
settings.Text = "ტემრინალი";
}
).GetHtml()
#Html.DevExpress().ComboBox(
settings =>
{
settings.Name = "TerminalID";
settings.ControlStyle.CssClass = "editor";
settings.Properties.TextField = "Name";
settings.Properties.ValueField = "TerminalID";
settings.Properties.ValueType = typeof(int);
settings.Properties.DropDownStyle = DropDownStyle.DropDown;
settings.Properties.IncrementalFilteringMode = IncrementalFilteringMode.Contains;
}
).BindList(LeaseReg.Models.Terminal.getTerminals()).Bind(Model.TerminalID).GetHtml()
#Html.ValidationMessageFor(model => model.TerminalID,null, new { #class = "validator" })
</div>
<div class="line">
#Html.DevExpress().Label(
settings =>
{
settings.ControlStyle.CssClass = "label";
}
).GetHtml()
#Html.DevExpress().Button(
settings =>
{
settings.Name = "btnUpdate";
settings.ControlStyle.CssClass = "button";
settings.Text = "დადასტურება";
settings.UseSubmitBehavior = true;
}
).GetHtml()
#Html.DevExpress().Button(
settings =>
{
settings.Name = "btnCancel";
settings.ControlStyle.CssClass = "button"; ;
settings.Text = "გაუქმება";
settings.ClientSideEvents.Click = "function(s, e){ document.location='" + DevExpressHelper.GetUrl(new { Controller = "MoveModel", Action = "Index" }) + "'; }";
}
).GetHtml()
</div>
#Html.ValidationSummary(true);}