Firstly, ease up on the “Trigger once” conditions. Use them sparingly, and only when needed. Only use them if the condition prevails over a number of game frames and you only want the actions performed once.
For example, mouse button is pressed is one it could be used for. But if you check a variable value and then change that variable value so it won’t meet the condition again, then a “Trigger once” isn’t needed.
I’ve given your attack combo a revamp. Here’s what a more streamlined version: