Woocommerce Single Product Page Error

Dear Experts…

Please help, I use woocommerce and recently I upgraded it to the latest version. Problems occurs that:
1. single product display won’t displayed correctly, and “related products” also won’t showed up anymore.
2. Plugin update always failed ! or the message will be “Connection lost or the server is busy. Please try again later.”
3. When processing, the respon sometimes respon” This site can’t be reached
http://www.mysite.com unexpectedly closed the connection. ERR_CONNECTION_CLOSED

Please help, really appreciate it.

https://wordpress.org/plugins/woocommerce/