Wrong reply address

Highlighted
Super Contributor

In office 365, User smtp address is santos@contoso.com and receives mail in this address but when he replies, his reply address is sentos@contoso.com.

 

if we reply to sentos@contoso.com, we got NDR

 

any known issue?  tnx

2 Replies
Highlighted
Mmmm...this is very strange: do you know if this user has additional aliases for his/her account?
Highlighted
no aliases except for santos@contoso.onmicrosoft.com

user is syn ched via AAD