To remove a rule or ip:
Find rule
grep 68.188.73.13 /etc/sysconfig/iptables
Delete rule (must be exact)
iptables -D INPUT -s 202.100.85.0/24 -j DROP
You can whitelist a ip to bypass any blocks and after restarting iptables you can find alist of rules here: /etc/sys-config/iptables