Press record on a call a colleague is already recording and Junior stops to ask:

Someone is already recording this call

This interview already has an in-progress recording. Create a separate call for your own recording, or view it live without recorder controls.

ChoiceWhat you get
View live recordingTheir transcript as it arrives. No controls to stop it, because it is not yours
Create new callYour own separate recording, alongside theirs

Which to pick

View live recording almost always. One recording of a call is what you want; two produce two transcripts, two summaries and a decision for whoever reads them later about which is authoritative.

Create new call when you genuinely need your own: you are covering a different part of a long session, or you need the call filed into a different project than the one they used.

Questions

Why does Junior only allow one recording per call?

Because two recordings of the same conversation is nearly always a mistake rather than an intention. Junior asks instead of silently doing it, so the duplicate is a choice somebody made rather than something discovered a week later.

Can I take over their recording, or stop it?

No. Whoever started it owns it, and only they can stop it. Watching live gives you the transcript without the controls.

It says it couldn't verify recording status.

Junior could not reach the service to check whether anyone else is recording. Retry first. It is usually a momentary connection problem. If it keeps failing, use Create new call and sort out any duplicate afterwards; recording something is better than recording nothing while you diagnose.

We both recorded it. What now?

Keep the better one and delete the other. The more-actions menu on a call has Delete call. Check which has the fuller transcript before choosing; whoever had the better audio setup will have the better version, and it is not always the person who started first.

The sidebar button says Live view rather than Record.

You are watching someone else's recording. Press it to open their live transcript. Your own Record button comes back when their recording ends.