It’s possible your snap failed to release because it fell foul of the store review process. This can happen if for example you are trying to publish a classic snap without having had classic confinement approved. It can also happen if you require additional priviledged interfaces.
We should probably expose this kind of thing in the storefront ( cc: @Lukewh ? ).
One thing you can do, is look on the “old” dashboard, and see if there’s any errors there. https://dashboard.snapcraft.io/snaps/(snapname) (you need to put the snap name on the end of the url otherwise you’ll get redirected to the “new” web storefront.
Also, you can snap install review-tools and then run snap-review (mysnap) against your snap, to see if it fails any store review processes, locally.