Your example comment is not actually a full answer for this site, but a hint on how to do it. A full answer would require more information from the user. We need to know what the network looks like (good description or diagram), the network device models, and network device configurations).
Look at the Network Engineering Question Checklist for the type of ...
I would also point out, if I can answer your question in the space (and limited formatting) of a comment, you're question is possibly of very low value/quality.
(for the record, this very answer is such a "comment quality answer")
There's nothing wrong with leaving a question unanswered if there is no explanation what has been done to resolve the problem.
Posting an answer that it was solved but the poster doesn't know how won't help much. There's no real benefit for others looking to solve similar problems, and only the person posting the question is able to accept an answer, so the ...
Unfortunately, these things happen. If you think the original question and your answer really are worth preserving, you can consider posting the question and answering it yourself. I don't think there's any other solution, there's no way to split the original question as if it was posted by the original poster.