It would be useful to see the printing just cut off on the left hand side.
I’ll wait for some US folks to chime in, but in just doing some searches now, I suspect this may be a counterfeit stamp - there were apparently many done of the 2017 USPS Flag stamp.
I’ll be curious to see what people say.
And btw, if people don’t know, counterfeit stamps are multi-billion dollar a year business & cost post offices those billions which they then pass on the costs to us, the users of stamps. That’s why post offices machine or hand cancel stamps.
And most counterfeits are very good & not obviously forgeries to the average person who thinks they’re buying real stamps.