Jul 27, 2022 11:48:24.070 [5744] DEBUG - TrayIcon::WindowProc received DisplayIcon timer message
Jul 27, 2022 11:48:24.070 [5744] WARN - Shell_NotifyIcon(NIM_ADD) failed: 0x80004005
You might want to use the command line parameter -noninteractive when starting PMS. It suppresses all errors which have to do with the regular task tray icon on Windows. (which is not used when running as a system service)

At least you have no messages about a damaged database file in your logs. So that is a good thing.
There is currently an issue being tracked about PMS becoming unresponsive after a few hours/days. Plex keeps crashing/closing - #110 by sa2000
(The process is not crashing per se, which unfortunately means that the watchdog in NSSM won’t catch it.)
Last thing I heard about that is there was an issue found with the Microsoft compiler/linker, which required working around it. The workaround is expected to become available in PMS 1.28.1.xxxx