Change User interface language back to English from Khmer

Changed the User interface language to Khmer to see if I could for a friend who uses Khmer. But now I can’t change back to English. Its now not an option…
Using 5.2 for 64bit Windows 10

What do you mean by ‘not an option’? Is it possible that you just don’t recognize ‘English’ when written like ‘pheasaeaangkles’ or ‘ភាសាអង់គ្លេស’ (from Google translate)? Can you choose any language? Can you reinstall LibreOffice?