radperf and radius returns challenge

I am trying to make a performance test for a radius server that sends challenge instead of Access-Accepted but radperf marks all responses as fail Total failed : 100 this is the command I used. radperf -q -s -a pap -c 100 -T test.rad -f user.csv -p 100 -r 1 -t 60 localhost:1812 auth testing123 what can I do? any help is highly appreciated.