Apple's SMS trash can

Is this a text message? I don't think it has been sent out yet. It's in the draft box.

Check whether the number is entered incorrectly and whether the network signal is unblocked.

You shouldn't send messages directly to the spam box in advance. If you were an instant chat tool, you wouldn't prompt this.

If it is a real email address, it will only show whether the email was sent successfully, and will not prompt the spam address.