Only one of my email adress works

Only one of my email adress works

Hello, i created 3 mail adresses, and only the first one that i created works the 2 others cant recieve my test mails.

I get 553 Relaying disallowed error when i try to send to one of those email adress.

In my admin panel all my adresses are green on the Entry/Exit Status so i dont see why only one of them works.

Does someone know where my problem is ?

Thanks in advance for your response.