Margin Too Wide on Kindle Reader

I used Scrivener as a quick and dirty way to turn a rtf into a mobi file, but the left margin is too wide.

I don’t have this trouble with other files. How do I fix it?

Are you able to override indents with the Formatting compile option pane? That would probably be the easiest way to solve any oddities like this, as you probably know. Otherwise I’m not sure what the problem could be, if it isn’t coming from the Formatting compile pane then it must be a problem with the text in the editor, which could be checked with the Ruler.

No, I can’t override it.

I’d check with the Ruler then. Since it came in from another program, it may have more indent on the left than you’d normally have. That should show up with the ruler handles.