For some reason when you're being attack it won't clear and prevents you from entering in commands. I'd put it on the bug board but it seems more like a 'by design' thing. Its just a frustrating way to eat a death + full loot when you had opportunities for your commands to go through but they were blocked.

Try help scrolling or scroll. The default is 24, but you can set it from 10 - 100 says the helpfile.

Set it to 100 after that happened. I usually do, just slipped my mind. Still, being that it defaults to 24 so every newbie has it at 24 and its just a bit buggy, would think it'd be good for everyone if it just went away when you entered combat mode.