After I can change the Month name from this thread https://forum.awareim.com/https://forum.awareim.com/d/8223>
I got new issue again when I use the "Date Format" in Attribute of BO is "dd MMMM yyyy" but I didn't got it if I use MM/dd/yy.
The issue is "Attribute has invalid format" but it works correctly when I delete the Locale that I created before although I use the date format is "dd MMMM yyyy".
What should I do to fix this issue if I create a Locale and the date format should "dd MMMM yyyy"?