Evaluate that variable one more time, so that its contents are also evaluated. This can be accomplished with the $eval() identifier, $eval(string,N) - it evaluates the string N times.
So if a variable %var contains $me just like that, using $eval(%var,1) merely evaluates it once to produce $me. If you want your own nickname shown you have to evaluate it an extra time with $eval(%var,2) which is exactly what you want to use in this case
Bear in mind you can also store the identifiers in your variable as $!duration() which evaluates once to produce $duration(). The $() identifier works in the same way as $eval() in case you're interested in shortening your code those 4 bytes