package unattended-upgrades 2.3ubuntu0.1 failed to install/upgrade: installed unattended-upgrades package post-installation script subprocess returned error exit status 137

After updating ubuntu's 20.04.1 packages, lots of error reports started to pop up, and one of those is this one. I dont know what it could be

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: unattended-upgrades 2.3ubuntu0.1
ProcVersionSignature: Ubuntu 5.4.0-45.49-generic 5.4.55
Uname: Linux 5.4.0-45-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.8
Architecture: amd64
CasperMD5CheckResult: skip
Date: Thu Sep 3 16:35:32 2020
DuplicateSignature:
 package:unattended-upgrades:2.3ubuntu0.1
 Setting up unattended-upgrades (2.3ubuntu0.1) ...
 dpkg: error processing package unattended-upgrades (--configure):
  installed unattended-upgrades package post-installation script subprocess returned error exit status 137
ErrorMessage: installed unattended-upgrades package post-installation script subprocess returned error exit status 137
InstallationDate: Installed on 2020-09-02 (0 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
PackageArchitecture: all
Python3Details: /usr/bin/python3.8, Python 3.8.2, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: N/A
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.2ubuntu0.1
SourcePackage: unattended-upgrades
Title: package unattended-upgrades 2.3ubuntu0.1 failed to install/upgrade: installed unattended-upgrades package post-installation script subprocess returned error exit status 137
UpgradeStatus: No upgrade log present (probably fresh install)