Confirmation of cashing a money order can be difficult. Here is some useful information from:
https://www.thebalance.com/track-a-money-order-315482
"When you pay with a money order and would like to know if your payment's been received and cashed by the right person rather than stolen, there’s no easy way to tell unless you speak with the recipient.
Unlike personal checks, money orders aren’t directly linked to your personal bank account, so you won't see any evidence of the money order clearing. However, you can track money order payments by placing a request with the money order issuer.
With most Western Union and MoneyGram, you can find out if a money order was cashed by calling a toll-free number. For USPS money orders (or to get more details from any issuer), you’ll submit a form and pay a modest fee for the tracking service.
After about 30 days, the issuer will either send a copy of the
endorsed money order
(showing who cashed or deposited it, and when) or a notice that the money order has not yet been cashed. If the money order
is still outstanding
, you should still have the option to
cancel it and get a refund
. The exact process varies from issuer to issuer."
Why don't you look on the government site ... get a tax account transcript to confirm the payment ...
You can get a return transcript from the IRS for free : http://www.irs.gov/Individuals/Get-Transcript