Sure - I'll take a shot.  I noticed that you have the date "23-12-15".  With the Year first. macOS allows for various international date formats. QuickBooks Mac predates many of these. We've tried over the years to expand the supported date formats but I'm wondering if this may be a bug with the YY-MM-DD format.  I know we were unable to support MM-DD-YYYY format as there isn't enough room in many of the date fields to accommodate the additional two characters and correcting for that across every screen in the product turns out to be a huge amount of work. 

Try setting your date format in System Settings to be MM-DD-YY and see if that fixes the problem.  The date should be either the last date you entered in a transaction or the current date depending on your Preferences settings.  

FWIW: The menu was called Preferences… in previous macOSs but as of some recent macOS version Apple changed it to be Settings… to better match iOS.  Apple actually went in and replaced the word "Preferences…" with the word "Settings…" at run time.  This apparently caused issues to Apple then stopped doing it. Which made for a very confusing situation. We've updated QuickBooks Mac to use the word "Settings…" in newer versions.