I was reading alot about this problem now but it seems theres still no awnser.
After 7 years i forgot my ESO account password for Age of Empires III Complete Edition multiplayer mode.
I tried to recieve an E-mail with the ESO Account tool on this site: https://esoaccounts.agecommunity.com/login.aspx?ReturnUrl=%2FAccountManagement%2FDefault.aspx
I used this tool for over 10 times and wait now about 2 weeks but i still do not recieved any E-mail.
And yes i checked my spam folder and i turned off my computer and turned it on again. haha funny…
I even deleted the game out of my steam library and bought it once again to get a new Key to make a new ESO account. This dont worked either. Now i bought this game 2 times and still cannot play it in multiplayer. I really want Age of Empires III to solve this problem.