Not all files are encrypted / unencrypted files synced to nextcloud-server

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1

Hi.
I’m using Cryptomator 1.14.2 (deb-1) on Ubuntu 20.04 with Nextcloud. Although eveythings seems to work just fine, I noticed that there are unencrypted files stored in the encrypted /d/-Subdirectories and synced to the Nextcloud server. There’s no running encryption task. I Emptied the vault, put back the data and it happened again. I really have no clue how to get into this. There’s nothing more special then space in the filenames or anything. Is this a known issue?
Example:

root@nextcloud:/var/nextcloud_data/User Name/files/CRYPTOMATOR/C-LEVEL# find . -name *.pdf
./d/GQ/GNY2DPHAG7DJYMUCCXUP5J53ADG7AV/jicuiDL_67k_JE0DyvprPEPgZlso5Gig1yo=.c9r/Werbung/Werbung 2016/druck_v2_druck.pdf
./d/GQ/GNY2DPHAG7DJYMUCCXUP5J53ADG7AV/jicuiDL_67k_JE0DyvprPEPgZlso5Gig1yo=.c9r/Werbung/Werbung 2016/druck_v2.pdf
./d/GQ/GNY2DPHAG7DJYMUCCXUP5J53ADG7AV/jicuiDL_67k_JE0DyvprPEPgZlso5Gig1yo=.c9r/Grafiken/Unterschrift.pdf

Thanks for your help!

cheers
mene