Did you write your note in MS Word (or WordPerfect) and copy and paste it into the Bunk Notes page? Sometimes, these programs replace the 'standard' characters (e.g., a straight apostrophe (') ) with non-standard characters (e.g., a curved apostrophe (’) ). These non-standard characters look nicer on the screen but are not recognized by the Bunk1 page and are replaced by a "?" in the text of the Bunk Note received by your camper.
If this is happening on you may wish to write your Bunk Note only on the web page or compose it in a text-only editor. Most Windows based computers come with Notepad. You can find Notepad in the Start Menu under Programs... Accessories.