This issue can happen, for example, if high-contrast mode is enabled in Windows, causing the field numbers to disappear. With high-contrast mode enabled, you must tweak the settings in Tools > Options > Record Display to get the fields and text to show up. Here are some steps you can take and adjust as needed:
Once applied, you should see the display of the record in the background change. If the text and fields still do not display as desired, try defining different colors for the Authority Window, Authority Text, and Authority Field.
Also, if bibliographic records are displaying correctly, you could tweak the three authority settings to match what you have set for the bibliographic records.