FreeRADIUS 2 traffic counter does not work

Question

I've added this block to radiusd.conf

sqlcounter monthlytrafficcounter {
    vcounter-name = Monthly-Traffic
    check-name = Max-Monthly-Traffic
    reply-name = Monthly-Traffic-LIMIT
    sqlmod-inst = SQL
    key = User-Name
    reset = monthly
    query = "SELECT SUM(acctinputoctets + acctoutputoctets) FROM radacct WHERE UserName='%{%k}' AND UNIX_TIMESTAMP(AcctStartTime) > '%b'"
}

and added the dictionary

ATTRIBUTE Max-Monthly-Traffic 3003 integer
ATTRIBUTE Monthly-Traffic-Limit 3004 integer

then added monthlytrafficcounter to authorize in /etc/freeradius/sites-enabled/default

but it doesn't work

The Max-Monthly-Traffic is defined in MySQL table radgroupcheck and the users were added to the group in radusergroup

Although a user has reached the traffic limit, he still can be authorized by FreeRadius