How to decay a violin note when it finally stops playing

Hi. Sorry if somewhere this has been answered, but ... in a piece I just finished that contained a violin track, I had no problem entering strings notes throughout the measures, and having the mixer play them legato, but when I entered the last note of the violin in the last measure, it continued playing at constant volume until the end of the measure, then stopped abruptly. In real life, a bowed violin would decay in volume and fade out smoothly when the violinist stopped bowing. How do I edit the score to get the mixer to decay that last note from normal volume to 0? I've tried reading up on single note dynamics, hairpins, etc. but somehow can't seem to understand how to do this. Could you just describe the steps? Thanks