1. Reopen the datepicker
If you select a date in the datepicker and _for some reason you want to immediately change that date you have to click outside the _field otherwise it will not reopen the datepicker (there is an animation example with the issue in the _first github link)
This is a known bug and the say that it has been _fixed in the nightly beta so it might be easy to _fix
https://github.com/fomantic/Fomantic-UI/pull/2002
https://github.com/fomantic/Fomantic-UI/pull/1508
2. Wrong display _format.
In the _field setup select Display Format as DD/MM/YYYY.
In the _form if you select the date in the datepicker it will set it correctly DD/MM/YYYY but if you write your date with the keyboard ex. 02/10/2022 (DD/MM/YYYY) it will change it to 10/02/2022 (MM/DD/YYYY) in the _field. (*if you write a date where the day is over 12 ex. 22/10/2022 it won't change it).
*For a very strange reason i had a very hard time posting this topic, every time a word starts with space and the letter _f when i save it gives me a 500 Internal Server Error and after some tries it bans my IP. That's the reason i have underscores before all lowercase _f