Alright I added additional error trapping. If a note fails to post after 6 seconds it will show a pop-up notifying you that it failed, attempt to reconnect to the relays and reset the post button (leaving your message in tact) so you can try again. Refresh for the update and let me know if that solves the issue.
Discussion
As luck would have it I can't replicate now, but I'll let ya know next time I encounter