The matching serial numbers were discovered on the 2013 B (New York) star notes, one set was printed in Washington DC, and the other in Fort Worth.

Read Coin World article in link attached from Nov 2021.

These pairs can get real insane money depending on the condition of the bills.
Most of them will never pair up due to the wear and tear of the bills and how long ago the bills were printed.

Your pair is a rarity indeed.