named-checkzone example.com /var/lib/named/master/example.com
rndc reload example.com
rndc dumpdb                       # dump whole cache
rndc flushname example.net        # clear example.net from cache
rndc flushtree example.net        # clear example.net and *.example.net from cache
rndc flush                        # clear whole cache

Manual edit of zone file:

rndc freeze example.com
vi /var/lib/named/dyn/example.com
rndc reload example.com
rndc thaw example.com

zone example.com/IN: journal rollforward failed: not exact
zone example.com/IN: not loaded due to errors.

systemctl stop named
rm /var/lib/named/dyn/example.com.jnl
systemctl start named