Asp.net mvc - Html Submit button not sent with post?

As in the title. I use this method for allowing more than one submit button per form and more than one action to handle them.

However - for some odd reason - all of a sudden my submit button doesn't get submitted with the form!? any reason why that would happen?

tested using IE, FF, Chrome - all latest

View code:

    <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Setup.Mvc.ViewModels.SignUpViewModel>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
    SignUp
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
    <% using (Html.BeginForm("SignUp", "SetUp", FormMethod.Post))
       {

    %>
    <%: Html.ValidationSummary()%>
    <button  type="submit" value="Register" name="ActionRegister" >Register</button>
    <button  type="submit" value="Cancel" name="ActionCancel" class="cancel" >Cancel</button>
    <fieldset>
        <legend>Account Information </legend>
        <dl>
            <dt>
                <%:Html.LabelFor(x=>x.UserName)%>
            </dt>
            <dd>
                <%: Html.TextBoxFor(x=>x.UserName) %>
                <%: Html.ValidationMessageFor(model => model.UserName) %>
            </dd>
            <% if (string.IsNullOrEmpty(Model.Provider))
               {    
            %>
            <dt>
                <%:Html.LabelFor(x=>x.Password)%>
            </dt>
            <dd>
                <%: Html.PasswordFor(x => x.Password)%>
                <%: Html.ValidationMessageFor(model => model.Password) %>
            </dd>
            <%
               } %