W: GPG error: http://repo.mysql.com trusty InRelease: The following signatures were invalid: KEYEXPIRED 1550412832 KEYEXPIRED 1550412832 KEYEXPIRED 1550412832

When you run sudo apt-get update, MySQL repository key has suddenly expired again.

Traceback: W: GPG error: http://repo.mysql.com trusty InRelease: The following signatures were invalid: KEYEXPIRED 1550412832 KEYEXPIRED 1550412832 KEYEXPIRED 1550412832

Fix

sudo apt-key adv –keyserver pgp.mit.edu –recv-keys A4A9406876FCBD3C456770C88C718D3B5072E1F5