Getting related entities ASP.NET WebApi OData v4 results in “No HTTP resource was found that matches the request URI”

I followed this asp.net tutorial by Mike Wasson, and managed to set up the related entities just fine, but when I applied this logic to my project the more complex entity relations (in that there are more of them; that’s the only difference) wouldn’t succeed in an OData call, I got a 404 with this payload:

Change User Password in ASP.NET Forms Authentication

I code in C# (ASP.NET) and am using Forms authentication.
I would like to know which is the best method to change a user password without using the asp:ChangePassword control.
I dont want to use the reset password method.
I just want to grab the password i have inside my textbox and replace it with my older password.
Please note that the PasswordFormat I use is passwordFormat=”Hashed”
Some code snippets would be helpful