I tried this:

"Customer wants to lear how to better talk in a company situation, and bring across their argument effectively"

Than had it choose what training would be fitting for this user: - Communication and Feedback - Leadership for Begninners - Soft Skills and Emotional Awareness

It picked always the third with an 80% confidence, while the answer should have been 1.

You sure the answer should have been 1? As a human I'd say I don't have enough information to answer this confidently, but "argument effectively" strongly suggests soft skills to me