In Better Call Saul season 6, episode 7, as the scam on Howard is about to unfold, Erin Brill asks Miss Falco from Provo to unmute and confirm she’s on the mediation call. Why does Erin do this?
There's an audible indicator that someone joined/left the call. This was triggered when Jimmy and Kim join using the pilfered details Francesca acquired.
Erin, hearing this, was concerned that someone had been disconnected from the call and was checking that all of the class representatives were still present.