The party line is that Audacity doesn’t reliably record Skype or any chat or conference service.
Skype in particular is vicious about turning the computer’s sound systems to do what it wants and what you want just isn’t considered. Sometimes it’s just unstable. “It worked last week and now it doesn’t.”
Some people go through months of podcasts and everything works just fine. Those people are looking at the rest of us wondering what’s wrong. Those people are unicorns.
If Skype went through an update in the middle it could just be set up differently now. If Skype needed to renegotiate the connection for any reason, it may have decided to change the settings. Impossible to know.The Skype part of the system is working, right? Both parties can hear each other?
If you just can’t find what happened, we recommend Pamela paid software or one of the other software packages that “knows” what Skype is and how it works. Fair warning don’t fall in love with software that insists on working in MP3 and you might pay attention to whether it will produce split tracks or not. Pamela takes care of all that with easy options.
http://www.pamela.biz/en/products/
https://forum.audacityteam.org/t/help-recording-with-a-mic-laptop-and-headphones/35068/6
Koz