Since your question is about this site i moved your topic from Android to Ranch Office forum, dedicated for such issues.
Randy Tong wrote:The post reply button appear now.
Good to know that
Look at the top left corner of that topic in your screenshot it didn't have any forum assigned to it so i added that topic to Android which resolved the issue for now. I wasn't in touch with the forum but it appears known bug. I'm sure smart brains are working behind to resolve the bug.
Not being assigned to a forum is not the problem. Over the past week or so I've had 3-4 times where I couldn't reply to a post. When I can't I go to other posts and look for the reply button, not there.
In other words, when I can't reply to 1 post I can't reply to any posts. The problem clears itself up overnight.