Some fonts (typefaces) don't support Unicode, or only partly support it. Evidently, whatever font you're using doesn't provide full Unicode support.

Having typed 20B5 + Alt x, and just gotten a square, you can select the square then use the Font selector on the toolbar to choose a TrueType or OpenType font that looks similar to the one you're already using. If that font provides full Unicode support, IIRC your square should change to ₵ - if it doesn't change, you'll need to retype 20B5 + Alt x.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

Can you please explain what you mean by IIRC the square?

IIRC is abbreviation for If I Recall Correctly.

Now, instead of typing 20B5 + ALT X, simply type ALT+ 8373. 8373 is the decimal value for the “CEDI SIGN” HTML entity. It is often preferable to use these decimal values because Word automatically chooses to format the typed code with a font that does include the corresponding glyph (character). To find out decimal values for HTML entities, go to http://www.mclean.net.nz/ucf/.
HTH.