IP restriction bug in TFTP Server

Hello,

I use the tool SolarWinds TFTP Server. I configured some IP Address Restrictions in the settings:

Important is the subnet from 10.239.1.1 to 10.239.255.254

Despite this configuration, a log shows that the IP address 10.239.77.0 is blocked, as we can see here:

Is that a known bug ?
Does anyone experience the same issue ?
Can I do something ?

I'm using version 11.2.1.60010