There are several synonyms you can use instead of "doing disservice to." One is "harming," which implies that the action taken has caused damage or detriment to someone or something. Another is "undermining," which suggests that the action has eroded or weakened the person or thing being affected. "Depriving" is also a viable option, as it conveys the idea of taking away something that is rightfully due or needed. Similarly, "jeopardizing" denotes a situation where the action taken puts something or someone at risk. Lastly, "disappointing" implies that the action taken failed to meet expectations or fell short of what was promised or anticipated.