If you need to update your media file or link, you can simply update the Media Asset. All existing trackable links will point to the new asset.
Go to Content > Media
Select the correct tab (My Media or Shared Media, depending on whether you or someone else created it)
Click on the Gear/Cog icon next to the Media
Click Edit
In the section "Replace this media with a new file?", upload a file or add a new link
Click Save Media at the bottom right