Welcome to the forum 
A quick search with the error and extension should lead you to here: The switcher stopped working (Manjaro versioning issue) (#72) · Issues · Romain / Night Theme Switcher GNOME Shell extension · GitLab witch points here: [Stable Update] 2021-09-04 - Kernels, Wine, Deepin, KDE Gear, Maui-Kit, Plasma - #23 by Yochanan
What version of the night time switcher are you using and from where is it installed?
Current latest working should be:
gnome-shell-extension-nightthemeswitcher 51-2
edit:
When you are on 52 (there was an issue and the package was rolled back) you need to downgrade:
https://wiki.manjaro.org/index.php/Downgrading_packages
Example
pamac install downgrade
sudo downgrade gnome-shell-extension-nightthemeswitcher
Depending on what you have in the cache you can choose what version you want to go back to, the stable version is 51-2