I have the same issue, not picking up the inbox message and the game tells me I need to read it to progress. Submitted a bug report about it but I've been unable to find a workaround. A possible temporary solution is running the story with another character - when I switched to an alt and started the story on it, the mail did appear inbox allowed me to continue. Doesn't help if you have a main you want to clear everything with, or you are running a single character.