I've moved your question to the InDesign forum.
What version of InDesign? What computer platform? Which PDF preset was used for creating the PDF file?
It would help if you could provide screen captures from InDesign and from Acrobat to show how the PDF doesn't reflect the InDesign file. Use the Camera icon in the edit window to attach screen captures.
Which font is affected?
Is that font embedded in the PDF? You can find that information with right mouse click on a page of the PDF in the context menu File Properties (or File Information) in the section Fonts.
If not, what kind of font is it? Is it a TTF? Does the font permit embedding? If not, you should exchange it with a font which allows embedding.