The code on your screenshot looks correct - is should pick one bullet instance with disabled=false.
The problem must be in some other event. Or maybe there are no disabled instanced. Try running the project in Debug Mode and check.
Oh, i just realized what i did wrong. Last time i did that code i place "is disabled" at the bottom rather that at the top, which caused to select a bullet that wasn't disabled. I recreated the code just for this screenshot and accidentally did it correct.
Thanks for helping me anyways!