deja-dup fails due to gpg issue

Lubuntu 18.04 64-bit with current updates. Backing up to external HDD via USB 3.0.

When attempting backup, I receive an error message stating:

"Backup Failed
GPGError: GPG Failed, see log below:
===== Begin GnuPG log =====
gpg: WARNING: "--no-use-agent" is an obsolete option - it has no effect
gpg: AES256 encrypted data
gpg: gcry_kdf_derive failed: Invalid data
gpg: encrypted with 1 passphrase
gpg: decryption failed: No secret key
===== End GnuPG log ==== "

Deja Dup package received a recent update, if I recall correctly. Deja Dup worked correctly up until today.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: deja-dup 37.1-2fakesync1ubuntu0.1
ProcVersionSignature: Ubuntu 4.15.0-118.119-generic 4.15.18
Uname: Linux 4.15.0-118-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.17
Architecture: amd64
CurrentDesktop: LXDE
Date: Wed Oct 7 12:05:28 2020
ExecutablePath: /usr/bin/deja-dup
InstallationDate: Installed on 2018-09-22 (746 days ago)
InstallationMedia: Lubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: deja-dup
UpgradeStatus: No upgrade log present (probably fresh install)