Some messages no longer appear on my smartphone
If the application storage on your BlackBerry smartphone is full or you have more than 65,000 email messages, PIN
messages, and text messages, your smartphone deletes the oldest messages from the message list. Your smartphone
doesn't delete saved messages.
If wireless email reconciliation is turned on and, in the message options, the Delete On field is set to Mailbox & Handheld,
email that you delete in the email application on your computer is also deleted from your smartphone.