I, too, have noticed this, on Snap version 25.0.6snap1 - 25 Apr 2023. I suspect this other post is the cause. The error seems to be that Collabora switched the service name from loolwsd to coolwsd, which broke Nextcloud Office, but unless someone posts detailed instructions on how to fix that exactly, there’s nothing fellow hobbyist can do, but wait for a new version that will work. Perhaps previous versions (on Snapcraft) might work. I wish us luck. Thanks.