CentOS Linux release 7.9.2009
spamass-milter-0.4.0-7.el7.x86_64

Tag in spamass-milter config file:

EXTRA_FLAGS="-r 8 -R SPAM_IS_NOT_ALLOWED_HERE -i
127.0.0.1,[2001:0db8:85a3:0000:0000:8a2e:0370:7334] -g sa-milt

Error message: systemctl status spamass-milter:

Ignoring invalid environment assignment

If the following command is directly fired on a prompt.

spamass-milter -r 8 -R SPAM_IS_NOT_ALLOWED_HERE -i
127.0.0.1,[2001:0db8:85a3:0000:1319:8a2e:0370:7344] -g sa-milt

Error message:

Could not parse "[2001:0db8:85a3:0000:1319:8a2e:0370:7344]" as a network

cat maillog:

spamass-milter[15169]: Could not retrieve sendmail macro "i"!.  Please add it
to confMILTER_MACROS_ENVFROM for better spamassassin results