Firewall Raw Rule not drop CIDR 16?

RouterOS Beginner Basics
1

Hi,
I’ve a script that ban IPs after 3 times they try access: the script simply add every single IP in an Address List.
Then, i have a this Firewall Raw Rule that simply drop this list:

/ip firewall raw
add action=drop chain=prerouting comment="DROP - Lista BANNED" src-address-list=BANNED

Now, if I manually add to this list, for example, this IP: 123.456.0.0/16
seems the Raw Rule doesn’t work because sometimes the script add an IP like 123.456.xxx.xxx
The log confirm there was some try from this IP, so the script is right, right?
IPs are externals, not LAN IPs.

So,
Why the Raw Rule doen’t block List with CIDR 16?

Thanks all!

RB4011iGS+
RouterOS v6.49.7 (stable)