This seems to have slipped through the cracks. The topic you mentioned (How to Set Up KBanking) does seem to be the only other relevant mention of snaps. I’ve added the snap tag here, in case someone else with more knowledge can take a look.
I don’t know how to tell if a new snap package has been generated, so reinstalling is probably worth testing. If that doesn’t help, you might try the appimage version, as also mentioned in that other thread.