Naven
Answers
Why is my message not sending?
Usually the connection, occasionally the screen. On Naven a message refused by the screen says so, with the category, at the time — so a message that simply will not go is a network problem rather than a policy one.
The distinction matters because the two look identical if a platform is vague about it. A silent failure leaves you guessing whether you said something wrong.
If it was the screen, you are told which of the twelve published categories it matched, and a second check reviews the refusal within the hour and withdraws it if it was wrong.
If it was the network, the message stays in the composer rather than disappearing.