Everclear 750 ml bottle measuring 610ml

Hey Reddit, I’m making limoncello and measuring my Everclear for the recipe. Does anyone know why a 750ml bottle would measure 610ml? I also tried ounces in case my scale was off with ml. According to google 750ml = 25.36 oz and my scale is showing 21oz for the bottle. Trying to figure out why my measurements of the bottle are so off. Thanks!