Post Office useless

Not the branch in Menlo Park or the PO call centre answers phones nor any response from a email sent to customer services. It seems like the post office are either re using tracking numbers or making errors when providing tracking numbers! Nobody can assist or provide answers or tell me where my registered mail containing VERY important documents are. Why some companies still insist on using Post office registered mail I do not know since I could predict that the mail will get lost!!!!