Rsync crashes rmfuse

[celadonfish]

So.. what I'm trying to do might be a bit ambitious. Basically, I am trying to sync the files from remarkable cloud to my Nextcloud server. Since fuse mounts into a directory, I can't sync those files directly. So I am trying to do a one-way sync with rsync:

rsync -av --progress --delete remarkable/ Nextcloud/remarkable

The Nextcloud desktop sync client then syncs the files to my Nextcloud server. But this seems to crash rmfuse and rsync. Rsync always creates the folder structure and copies the first "level" of files but then stops before copying anything within folders.
The same happens when I one-way sync to another local folder, so it's probably not related to the Nextcloud desktop client. Here is the end of the output of rmfuse:

unique: 420, opcode: READ (15), nodeid: 8, insize: 80, pid: 57215
DEBUG:rmfuse.fuse:Reading from 8 at 0, length 1255
   unique: 420, success, outsize: 1271
unique: 422, opcode: RELEASE (18), nodeid: 8, insize: 64, pid: 0
DEBUG:rmfuse.fuse:Releasing inode 8
   unique: 422, success, outsize: 16
unique: 424, opcode: OPEN (14), nodeid: 5, insize: 48, pid: 57215
DEBUG:rmfuse.fuse:Opening inode 5 with flags 32768
DEBUG:pyfuse3:Calling fuse_session_unmount
DEBUG:pyfuse3:Calling fuse_session_destroy

Is there anyway I could debug this further?