"Write something" box missing as an option on other's Facebook page on my Iphone

Until about 1 week ago I was able to post to my friend's Facebook page by clicking on the "write something" box but all of sudden that box disappeared. Now, my friend's pages are formatted a bit differently and the "write something" box no longer appears, and I'm unable to write on anyone's page. I have deleted my Facebook app and downloaded the latest version. I'm able to post on my laptop using the "write something" box, but that does not appear on my Iphone anymore. I cannot figure out what happened.