Raspbbery: Unrecoverable error {"error": "file or directory not found error

no, just use this one as a source for the --mount of identity to the /app/identity in your docker run command.
To change it, docker stop -t 300 storagenode, docker rm storagenode, delete the config.yaml from the storage location and run it back with all your parameters include changed one: https://documentation.storj.io/setup/cli/storage-node#running-the-storage-node