How to update the published asset in marketplace

I have uploaded a mobile application to the demo marketplace. It’s already published and showing up to the users. Now, I have updated the application, which has changed its preview code. Also, to show the UI changes, I want to change the uploaded images/text on the marketplace. How could it be done?

When I click on the asset, it opens the marketplace listing. On neither of the pages can I see an edit button via which I can make the changes. So, please guide me on how to update the already-published assets?

I just found out that I have already asked the same question in a previous post: How to update the app listed on marketplace

Can anyone guide me!