I am a Tour Guide, and recently a member PMed me who has had 3 books lost in the mail.  All 3 books had USPS DC on them, and 2 of these books were mailed on the same day.  What can she do?  Is there someone she can contact about this issue?  She has been told before that it must be her wrapping, so she has improved it.  But I am not sure that's the issue. Any ideas or suggestions would be very helpful!  

I think there's not much she can do in the way of recouping her credit because you have to use PBS DC in order to get your credit guaranteed.  She could file a lost package claim with USPS - not sure what kind of luck she'll have with that though.  There's a form she can fill out at the PO.