(debconf passthrough frontend loop) package shim-signed 1.33.1~16.04.4+15+1533136590.3beb971-0ubuntu1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 128

debconf window opened but was blank and the installation stopped. I had to force close it and quit installation midway.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: shim-signed 1.33.1~16.04.4+15+1533136590.3beb971-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-141.167-generic 4.4.162
Uname: Linux 4.4.0-141-generic x86_64
.proc.sys.kernel.moksbstate_disabled: 1
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
Date: Sat Feb 16 12:04:41 2019
DistributionChannelDescriptor:
 # This is a distribution channel descriptor
 # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor
 canonical-oem-somerville-xenial-amd64-20160624-2
EFITables:
 Feb 14 20:10:27 divij-Vostro-14-3468 kernel: efi: EFI v2.40 by American Megatrends
 Feb 14 20:10:27 divij-Vostro-14-3468 kernel: efi: ACPI=0xa8925000 ACPI 2.0=0xa8925000 SMBIOS=0xa93d6000 SMBIOS 3.0=0xa93d5000 ESRT=0xa9361598
 Feb 14 20:10:27 divij-Vostro-14-3468 kernel: esrt: Reserving ESRT space from 0x00000000a9361598 to 0x00000000a93615d0.
 Feb 14 20:10:27 divij-Vostro-14-3468 kernel: Secure boot MOKSBState disabled
ErrorMessage: subprocess installed post-installation script returned error exit status 128
InstallationDate: Installed on 2018-05-25 (266 days ago)
InstallationMedia: Ubuntu 16.04 "Xenial" - Build amd64 LIVE Binary 20160624-10:47
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.5
 apt 1.2.29ubuntu0.1
SecureBoot: 6 0 0 0 1
SourcePackage: shim-signed
Title: package shim-signed 1.33.1~16.04.4+15+1533136590.3beb971-0ubuntu1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 128
UpgradeStatus: No upgrade log present (probably fresh install)