Sorry, I’m stumped. In Settings → Advanced Settings, confirm that Asterisk Log Dir is correctly set.
There have been several threads started in the last 3 days related to logging having stopped.
https://community.freepbx.org/search?q=logfiles
(sort by latest post).
I suspect that they might have been caused by
but there were also some security updates affecting logs.
With luck, you’ll find a clue there. Otherwise, submit a bug report.