May have been shaved down to be used as a dime in a vending machine. I have found a couple over the years.
I use to smashed them down to the size of a quarter, put two of them together, and they would work in quarter vending machines . Those were the good old days ...
You're coin is damaged, it's what us collectors call PMD (Post Mint Damage), it's worth 1 cent and no more. Errors produced by the mint can be pretty easily identified by seasoned collectors. In general, they can be categorized within a specific, defined type since most of the processes that create them are well known.