Decryption not work

Nextcloud version:
Operating system and version: Archlinux ARM (armv7l), Kernel 4.9.63-1-ARCH
Nginx version: 1.12.2
PHP version: 7.1.11

Hello. I tried decrypt all files with
# php -f console.php encryption:decrypt-all

Encryption disabled, but files not decrypted.
# nano somefile.png
HBEGIN:oc_encryption_module:OC_DEFAULT_MODULE:cipher:AES-256-CTR:signed:true:HEND------------ …

Logs is empty. Old files not available to download and not preview. Please, help recovery files.

@bjoern can you help?

Same thing here on Nextcloud 16.0.3. Did you ever solve this?