Multilingual Megamenu not displayed when Switching Language

Hi,
I would like to set-up a site with 2 / more languages using BT_Arise2 Template with T3 Framework.
I think I have created all the Menu, Languages, Style according to the guides.
When I get into the site, Mega menu is displayed correctly.
As soon a I switch language, the Megamenu disapear and if I refresh the page, it is displayed again using the correct language.

I may have missed Something, but not able to figure out what.

Joomla Version : 3.6.4
T3 Framework Version : 2.6.1

Any advice?

Many thanks