I can't find anything that indicates that your account is deviated or lacks permission to post (especially as you've recently submitted). Try submitting again or tomorrow and see if it wasn't a one-off server flippage. We've been having some random bugs, so maybe that might've just happened while you were trying to submit. Just make sure you save a copy of your summary and save your coding so you don't have to do that all over again every time the archives wonk out.
If it doesn't work again, let me know and I can give the admins a jingle.