I added an answer to a question that was some time ago resolved in the comments only, as it just got another low-quality answer, and to have it resolved.
It seems that was not the correct thing to do, but, being new, I don't have any reference and I couldn't find any hint how to handle the case in the Help center.
Should I instead have flagged the question, vote to close it perhaps? Is the question useless or invalid after the Op solved it through the comments?