Welcome to Karma ownership. Depending on the outside temperature, terrain and driving style most Karma owners see between 30 and 45 miles per charge. 35 miles per charge is pretty typical for me as well. When it's cold it's even lower and in ideal conditions I can do well over 40.
50 Miles Range was a marketing myth. Fisker's range Guess-o-Meter is worse than most, and that's saying something.
Brent