An "unclaimed" tax refund differs from a lost refund.
Institutions may have different definitions of dormant account, lost account or unclaimed assets.
Around 1928 an apparition of an ancient Egyptian priestess was reported, and a newspaper reward for an overnight stay went unclaimed.
The IRS checks its records and the Social Security number of any claimants of the unclaimed funds prior to paying.
When I checked with the Sentinel, they told me the subscription remained open but there weren't any papers lying around unclaimed, yet you said there wasn't any forwarding notice filed with the Post Office.