/ip firewall address-lists
add name=block-this address=220.127.116.11
This creates an address-list named "block-this" that has one item on it: the IP address 18.104.22.168
/ip firewall filter
add chain=input src-address-list=block-this action=drop
This drops all traffic from addresses that are items on the "block-this" address list.
If you paste that in as is, you're blocking that IP address. The advantage of using an address list is that if you ever want to block a second, third, or more IP addresses, you just add them to the address list instead of having firewall rules that block just one single IP address.
http://wiki.mikrotik.com/wiki/Manual:IP ... dress_list
With your edit the rule you applied says "drop all traffic from IP addresses that are items on an address list named '22.214.171.124'". No such address list exists. If you wanted to have a firewall that directly refers to the IP address rather than using an address list:
/ip firewall input
add chain=input action=drop src-address=126.96.36.199
I prefer the address list approach because it scales better for the future.