It could probably be that your server/hosts takes a bit time to contact wordpress api.
This only applies if you have your own server or vps, if not, ask your host admin for this
1. Ping api.ww.wp.xz.cn, it will be 72.233.56.139, if it is reachable then,
2. Edit your host file vi /etc/hosts
3. Add in this line
72.233.56.139 api.ww.wp.xz.cn
4. Save :wq
Then check if it works. NOTE: this is the method that works for me, i cannot guarantee that it will work in your case. Thanks and God Bless.
