It sounds like you are expecting to be able to access the symbolic characters of the Sonata OpenType font via keyboard. Unfortunately, it doesn't work that way. Unlike the old Type 1 fonts, OpenType fonts are normally Unicode encoded. As such, ASCII keyboard keystrokes don't map into the font font. You need to be able to enter the Unicode values for the symbols. If you are using software such as InDesign or Illustrator, you need to access the Glyphs palette to fully and properly access all the symbolic characters. For other applications, there are often symbol palettes that provide similar services.
-Dov