[ci skip] Add changelog entry for #4712
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 419859f..1a0af5a 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -43,6 +43,7 @@
 -  Fixed a bug (#4679) - :doc:`Input Library <libraries/input>` method ``ip_address()`` errors with a matching ``$config['proxy_ips']`` IPv6 address.
 -  Fixed a bug (#4695) - :doc:`User Agent Library <libraries/user_agent>` didn't load the *config/user_agents.php* file when there's no ``User-Agent`` HTTP request header.
 -  Fixed a bug (#4713) - :doc:`Query Builder <database/query_builder>` methods ``insert_batch()``, ``update_batch()`` could return wrong affected rows count.
+-  Fixed a bug (#4712) - :doc:`Email Library <libraries/email>` doesn't sent ``RSET`` to SMTP servers after a failure and while using keep-alive.
 
 Version 3.0.6
 =============