Trying to create members in a Partial View, but something isn't right

With the code below, i get the following error

CS1501: No overload for method 'RegisterMember' takes 1 arguments

Reference documentation: http://our.umbraco.org/Documentation/Reference/Querying/MemberShipHelper/ ;

Umbraco v. 7.1.4

@inherits Umbraco.Web.Mvc.UmbracoTemplatePage
@using Umbraco.Core;
@using Umbraco.Core.Models;
@using Umbraco.Core.Services;
@{
    var message = "";

    if(IsPost){
        if (Members.GetByEmail(Request.Form["customerEmail"]) == null){

            var memberModel = Members.CreateRegistrationModel();

            memberModel.Name = Request.Form["customerName"];
            memberModel.Email = Request.Form["customerEmail"];
            memberModel.Password = Request.Form["customerPassword"];

            Members.RegisterMember(memberModel);

        } else {
                message = "User exists";
        }
    }
}