Sorry for the fire drill. Now I see it.
Topics are locked by the owner when they think they have found the answer to the query and also to stop spam. Like your topic in my opinion has been answered by @JeromeTash. Now it is better that you go ahead and lock this topic if you are satisfied with the answer. Otherwise this topic will get spammed and later on might get deleted by the moderators.
Yes, the previous post is locked. But this post needs to be locked by the moderator, right? I can't lock it myself. In the previous post, I wanted to lock it myself, but I won’t be able to lock it.