in staroffice, i am changing font, size, style and etc., but is not save.

in staroffice, i am changing font, size, style and etc., but is not save.
typing text only scave, formatting style is not apply,

when the file is save, after closing,
when open the same file its having default formatting,
i am again changing formatting.

StarOffice is completely separate obsolete product by StarDivision (and later by Sun), completely unrelated to LibreOffice (except for some historic aspects). How your question is related to LibreOffice?