A family of Microsoft word processing software products for creating web, email, and print documents.
Check if there are any custom tab stops on the horizontal ruler (View > Ruler).
If you have inadvertently added a tab stop, any default tab stops will be cleared (ignored) on the right of the custom one. See screen shot below.
For more on tab stops in general, see http://wordfaqs.ssbarnhill.com/SettingTabs.htm.