R5-D4 Quest issue with defeat 5 enemies with Jawa Engineer

Hello, I 'm trying to do the quest in R5-D4 for "Defeat 5 enemies with Jawa Engineer. After several attempts to defeat 5 enemies using Jawa Engineer, it is not being counted. Am I doing something wrong, or is the description not entirely correct? I am only using Jawa Engineer. I also tried one attempt together with Chief Nebit, but that did not work either.