Also note that a recent default Ubuntu installation has only the main repository enabled, and Jitsi Meet needs packages from universe . Check your /etc/apt/sources.list file, and if universe is not present refer to Ubuntu’s documentation on how to enable it. (Usually it amounts to copying the main lines and changing to universe .)
@ant thanks, but it would be more helpful if you post the error that you’re getting from apt. What web servers did you have installed prior to jitsi-meet? So there was Apache, but was it working OK? Did it get stuck on Apache reload? Did you get any errors for Prosody? The postrm could get some QA love and I’m looking at it, so any details would be welcome.