The first thing you should do is to firstly analyze why Facebook is not responding on your iPhone. If you're not able to identify the problem then the most likely reason why Facebook won't open is that it's struggling to connect with the Facebook server. This means that either Facebook has changed the way it connects with the server, perhaps through a recent update, or that your iPhone has a problem connecting to the server. If you still have Facebook not responding on your iPhone then you'll need to firstly uninstall Facebook from your phone, and then try & reinstall it again. This may be all you need to do in order to get Facebook working again on your iPhone, but if not then you'll need to search for the Facebook server issue and see whether it's an iPhone-specific problem or not.
The other way you can help Facebook not responding on iPhone issues is to firstly attempt & fix the Facebook application itself. However, if you do have the official Facebook application on your iPhone, then you should be able to fix the Facebook problem by deleting the Facebook application and then re-downloading it. If you do this, you'll effectively be solving two problems in one - by firstly allowing Facebook to run properly again, and secondly by giving Facebook access to your Facebook account data so that it can fix the Facebook issue.
Read more here:- https://www.datarecovo.com/facebook-app-not-working-on-iphone/
https://datarecovo.hpage.com/fix-issues-with-the-facebook-app-on-iphone.html
http://datarecovo.populr.me/fix-facebook-not-working-on-iphone
https://datarecovo.bigcartel.com/how-to-fix-issues-with-the-facebook-app-on-iphone
https://educatorpages.com/site/Datarecovo/pages/facebook-not-working-on-iphone-today-7-fixes?
