Field checkbox (Binding ViewModel) does not work in View - Asp.net Core MVC

I have a bool field "System Default" in which a Binding is done with its respective ViewModel. Whenever the view is loaded, it looks like false but when I go with Break Point, ViewlModel's field is true ...

<divclass="col-md-5">
  <div class="checkbox-custom checkbox-primary">
    <label asp-for="PadraoSistema"></label>
    <input asp-for="PadraoSistema" disabled />
  </div>
  <span asp-validation-for="PadraoSistema" class="text-danger"></span>
</div>

How do I fix this? Hugs to all !!!!!