menu not switching language or location

hi
i have a WordPress multisite, one in English and the other in Arabic and i’m using multilingual press for translation and linking , the problem is that when i use the language switcher to go from Arabic to English the menu doesn’t change language nor position only the content change but when i go from English to Arabic it works fine ?????? i am using a child theme for the English site and the original theme for the Arabic site
note:the problem doesn’t exists when i use twenty-fourteen theme

https://wordpress.org/plugins/multilingual-press/