When the away team beamed down to Regula 1 space station, Uhura continued her hails. Right around the time Kirk found Checkov and Terrell, Uhura completely loses her mind "Please acknowledge signal....PLEASE?!" To which Saavik acknowledges and says they're alright. Was there an open com channel that maybe she heard Kirk say "Oh my God!"? Did Spock or Kirk forget to tell Uhura to stop signaling the space station, I mean Spock was JUST standing there the whole time...
Didn't you know that Uhura was paid by the hail? But more likely it was to contrast with the later scene inside Regula itself, where communications were suddenly spotty.
She was trying to contact station personnel that might be surprised by (and belligerent to) a three person Starfleet team with phasers just beaming in out of nowhere so she can tell them, "Relax, these are good guys, don't come out screaming and waving meat cleavers!" Of course, there was no one to contact, but there was no way to be sure of that until after the team had a look around, and no way to be sure the team hadn't suffered the same fate until Saavik called back and told her they were all right. Nothing about the situation is especially funny.
In the 23rd century, they haven't invented call forwarding yet. So the people in the genesis cave could not hear Uhura's plaintive cries.
"Commander Uhura, this is Lt. Saavik. We're all right. Please stand by. Out." Uhura's facial expression was priceless here and, yes...funny.