language urls are redirecting to default language

I am having a serious issue on my multilanguage site suddenly which was working fine before. Some of the language site urls are now defaulting/redirecting to the main default language.

http://www.ungrandoui.com/pt

the portuguese version feature links for example revert to the english version. this is happening for the french version as well.

can you please help?!

thanks,
tarik

https://wordpress.org/plugins/qtranslate/