Not able to post an answer?

Hi, wanted to ask a possibly stupid question..
After opening a thread with a previous question of mine, I can’t reply to the answer given or even use the “Answer the question” option. Every time I hit submit the post just disappears.
have tried different browsers, tried logging out and the logging back, clearing the cache, restarting. Been trying for a couple of days now. Any possible suggestions?

Thanks in advance for your time!

**Oh forgot to mention, after copying my answer that disappeared, I reposted the same one, it sais my answer is duplicate of a previous one and won’t be accepted!