Email other language

Dear,
My site is in english and japanese
I have successfully enable WPML for UM and I have created a folder under public_html/wp-content/themes/Divi-child/ultimate-member/email
Website is https://golanguages.online/

I have 2 folders, one /en_US and one /ja (for japanese), both templates look ok…

Then I tried to register….but when user is created, it does not send email in japanese…no email is sent at all….

Is there sth I should do more?

Thank you,
Pierre