Problems while transfgering item's from season 17 to normal

Hello , I’m french , I use reverso fot helping me .
Ok Season 17 just ended in europe 18 august , I found my character in normal mode, and so I started transferring the contents of my safe via the mailbox last sunday , and today I wanted to continue , but bad surprise , the mailbox button no longer appears , I still had a good hundred objects , I am disappointed , is it possible to restore this message in the mailbox .
Thank you for all the help you can give me.