The message you have included is a warning that is associated with a Failed Listing. There should also be a failure notification as the Warning message you note would not prevent a listing from posting in and of itself. It is very likely that there is also a corresponding failure notification. If you hover over the My Account menu, you can then click on the red number (this is for failure notifications) and you should be able to see a corresponding message for the item where you encountered this.
We are aware of the issue that generates the warning and our engineers are looking into that, however if you are unable to locate a failure message or need assistance with the noted issue, please feel free to file a support case from under the Help tab of the site letting us know which listing you have run into difficulty with and the error message involved (please leave the notifications in your account for our review) and our support team will be happy to assist you further.