Submit does nothing for "Make your Apple ID and primary email address one and the same"

Hello,

My Apple ID is currently xxx@me.com

My primary email address is currently yyy@zzz.fr, and has never been used as an Apple ID

I would like to use my primary email address as my Apple ID. But when I click Submit for on "Make your Apple ID and primary email address one and the same", nothing happens, and no error message is displayed neither.

Any idea ?

Regards.