Is this happening with just the one font or are all fonts (Postscript, Open Type or True Type) affected? Is it possible to open the file on another computer with the same version of InDesign and OS to see if the font has issues or it is being caused by your updated InDesign?
can you show the Type > Find Font… panel with that font selected and More Info showing?
Also test the following:
Disable Suitcase 21.3 temporarily.
Install the font by moving the font files to the Fonts folder of your InDesign Application folder.
( ACP )
Sreen shots attached. The first with Suicase managing the fonts and the second where the fonts are installed in the InDesign font folder. The results were the same. The font displays as per the first screen shot.
However, the font options in the style sheets changed when installed in the InDesign folder. The numbered options, for example Helvetica Neue TI 45 Light were still there but did not work. However, selecting a new option Helvetica Neue TI Light, displayed correctly and the same applied to all of the weights in the font.
Thanks for the assistance. Not sure what's causing the problem.
Hm. I'm a bit confused now. Let's sort this…
"Sreen shots attached. The first with Suicase managing the fonts and the second where the fonts are installed in the InDesign font folder. The results were the same. The font displays as per the first screen shot."
That is your first screenshot; I did some annotations:
What is the situation here?
You said Suitcase is enabled and manages the fonts. Does that mean that Suitcase provides the Helevetica Neue Type 1 fonts? If this is the case, the same fonts are also made available through a Document fonts folder at the same time.
Perhaps this is the real issue?
The fonts are installed two times at this moment?
From Suitcase AND from the Document fonts folder.
Please do the following:
Post a screenshot of the contents of the Document fonts folder.
( Property "Path" in the Info section is showing "Document-installed font", so InDesign has access to a Document fonts folder. )
 Check Suitcase and try to remove the access to Helevetica Neue from there. Could be that the Helvetica Neue in Suitcase is the one from your Mac OS system. This one would be the wrong one. The Helvetica Neue from the system is not a PostScript Type 1 font.
 Move the Helevetica Neue PostScript Type 1 fonts out of the Document fonts folder and move it to the Fonts folder where your InDesign Application is installed.
( ACP )