I Have New Message Notifications But Don't See the Messages

New letters from new people expire after 24 hours unless you reply. Otherwise, they disappear forever! 
If you haven't logged into the app in awhile, it's likely you'll have multiple new letter notifications but no new letters to view (again, once new letters expire, they disappear forever). 
Don't worry - you can avoid this completely by checking the app at least once a day and replying to new letters  While you wait for new letters,   Write A New Letter to find even more Pen Pals faster!

Tip: Since new letters expire after 24 hours, make sure you check your letters at least once a day to prevent missing out on new friends!