When you send a check to another party, you can trace its status through your bank. The same is true when you send a postal money order through the mail. The United States Postal Service allows you to check on whether or not the money order was cashed. Once you know it was cashed, you can then use this proof to ask the recipient for information on the status of your order or request.
Visit your local post office and ask for Form 6401. Fill out the form completely, including the money order number, your name and address (the purchaser), and the recipient information. Be sure to have a copy of the money order stub and receipt to hand in with the form.
Submit the form to your postal representative along with the form filing fee. The representative will mail the form to the United States Postal Service unit that handles these inquiries. That office will perform a check on the money order number, pull up a copy of the paid money order if it was cashed, and mail you the information. If the office determines that it was lost and has not been cashed after 60 days from the date it was purchased, a representative will cancel the old money order and issue you a new one.
Visit the United States Postal Service's "Damaged, Lost, or Stolen Money Orders" website and click "Money Order Inquiries" to e-mail a USPS accounting representative directly regarding your money order issue if you have additional questions.
If someone other than your recipient somehow deposited or cashed the money order, contact the bank that cashed the money order to report the situation regarding the account holder. If the bank cashed the money order even though it was written to another party, the bank may be on the hook to refund your money directly. You may have to contact your local authorities or file a case in small claims court to resolve the matter.