I think I already faced this issue and I have the solution. Following the update of Kstars, the catalogs needs also to be updated. Just go to the "data manager" and update all the catalogs of objects that need to be updated.
Note that it can also happen without any software updates, check the catalogs to get sure they're all fine before searching something.
Valentin
150P and 72ED with ASI 071 MC pro
Guiding with qhy 5L-II-m and ASI 178MC
HEQ5 pro with EqMod
Kstars Ekos on lenovo thinkcenter with Linux Mint 21