After moving an asset to a new folder, you are unable to see the asset in the tree, or see duplicates of the asset in both the new and old location. Occasionally, this may occur even when you have not recently moved the asset.
Sometimes when an asset is moved from one folder to another, it may not display correctly in the navigation tree. This is generally due to a caching issue. Try refreshing the browser or logging out of your Marketo instance, then logging back in. If this does not clear the issue, contact Marketo support to have us clear the tree cache for your instance.