Waiting time in Asterisk queue?

Question

Asterisk

Good afternoon!
FreePBX 14.0.16.4
Asterisk Version: 13.37.0

You need to get the response time in the queue in the dialplan, but the problem is that there is a group in front of the queue in which, if there is no response, it goes to the queue ..
$ {CDR (start)} I always have $ {CDR(answer)} which makes it hard to figure out how long the person was waiting in line...
Tried to use ${ANSWEREDTIME} but it turns out to be empty...
${CDR(duration)} is always equal to ${CDR(billsec)}

What to do? maybe some advice?