HiDrive-WebDAV - iOS - Numbers

I’m using Strato Hidrive via Webdav on my iOS devices (actually 17.5.1). When editing Numbers tables, after a short time I always get the message “table deleted, this table was deleted from another location” and “close”. The file is then saved, but has to be reopened each time.
Does somebody has any idea?

really, no idea? :frowning: