Thanks for your great question
Firstly, you said here that you has this set up as your Membership Options Page?
The Member Options page is assigned to
https://sumigni.com/member-pages/my-account/
This is an incorrect setup. This should be your Login Welcome Page (Dashboard -› s2Member® -› General Options -› Login Welcome Page), which will be restricted to users that are not logged in. the Login Welcome Page is the equivalent of the My Account Page. The Membership Options Page is where your s2Member buttons/Pro Forms should be at.
Find more info on this in Dashboard -› s2Member® -› Quick Start Guide.
When that particular page loads, it will default to the bottom.
It will load correctly if
1. one of the the two shortcodes are removed
2. a user is not signed in, thereby not displaying the profile form
3. I turn off all javascript in my browser (FF 17.0.1)
It will load incorrectly when
1. both shortcodes are entered into the backend.
2. and displayed on the frontend
Any thoughts where the conflict may be coming from
s2Member’s shortcodes generally are not meant to be put with other shortcodes into a page. This is because s2Member reuses the name/id attributes in one form to another. Therefore behavior like this is to be expected if you do put multiple Pro Form / Button shortcodes into one post/page.
Instead of having both shortcodes in the same page, I’d recommend instead using the Popup s2Member Profile feature available under Dashboard -› s2Member® -› General Options -› Member Profile Modifications. You could also move your Billing Modification Form to a different page as well. Any way that you can get these two shortcodes separated should do fine.