Please see the image below. I live in Australia and would like dates displayed DD/MM/YYY. This is formatted correctly in the base as seen in the support image. My interface displays the date correctly, however on my colleagues, it displays it as MM/DD/YYY. The most unusual part of this is that there are multiple dates and dates of birth in this interface and base, and this is the only value that does this.
The date format is determined by the browser language settings (when you select “local” on a date field), so my guess is that your colleague has different language settings compared to you (either correctly because they are somewhere else in the world or perhaps in error).
The answer is to fix the date to “European” for DD/MM/YYYY format if you want everyone to see that irrespective of their location/browser settings.