I just successfully setup the Hybrid migration for office 365 on my exchange 2010 server on premise. i migrated two mail boxes to office 365, that was successful as well. i can route messages back and forth between the migrated accounts and the on-prem accounts. then i created a new account on office 365, when i try to communicate with that account from my on-prem emails i get a bounce-back error saying the account doesn't exist. but i receive emails from from the account. what could be the problem.
N.B: as per dns:
1. my mx records are pointing to the on prem server.
2: I have autodiscover pointing to my onprem as well.