Can't install and uninstall packages, can't also remove dde

So I installed Deepin Desktop Environment and got an error while installing but continued anyway, I later on decided I will remove it but then it may not be removed, then I started doing other commands such as sudo apt install -f and it showed me this

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  deepin-anything-server
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
2 not fully installed or removed.
After this operation, 469 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 538850 files and directories currently installed.)
Removing deepin-anything-server (5.0.1-4) ...
userdel: user 'deepin-anything-server' does not exist
Failed on delete user deepin-anything-server
dpkg: error processing package deepin-anything-server (--remove):
 installed deepin-anything-server package post-removal script subprocess returned error exit status 1
dpkg: too many errors, stopping
Errors were encountered while processing:
 deepin-anything-server
Processing was halted because there were too many errors.
E: Sub-process /usr/bin/dpkg returned an error code (1)

I also tried sudo apt autoremove which showed me this

Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
 deepin-anything-server
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
2 not fully installed or removed.
After this operation, 469 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 538850 files and directories currently installed.)
Removing deepin-anything-server (5.0.1-4) ...
userdel: user 'deepin-anything-server' does not exist
Failed on delete user deepin-anything-server
dpkg: error processing package deepin-anything-server (--remove):
installed deepin-anything-server package post-removal script subprocess returne
d error exit status 1
dpkg: too many errors, stopping
Errors were encountered while processing:
deepin-anything-server
Processing was halted because there were too many errors.
E: Sub-process /usr/bin/dpkg returned an error code (1)

Is there any solution to this? I can't also install Synaptic since it gives me this

Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  libept1.6.0
Suggested packages:
  dwww menu deborphan apt-xapian-index
The following packages will be REMOVED:
  deepin-anything-server
The following NEW packages will be installed:
  libept1.6.0 synaptic
0 upgraded, 2 newly installed, 1 to remove and 0 not upgraded.
2 not fully installed or removed.
Need to get 701 kB of archives.
After this operation, 3,194 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://ph.archive.ubuntu.com/ubuntu focal/universe amd64 libept1.6.0 amd64 1.1+nmu3ubuntu3 [79.6 kB]
Get:2 http://ph.archive.ubuntu.com/ubuntu focal/universe amd64 synaptic amd64 0.84.6ubuntu5 [622 kB]
Fetched 701 kB in 2s (294 kB/s)   
(Reading database ... 538850 files and directories currently installed.)
Removing deepin-anything-server (5.0.1-4) ...
userdel: user 'deepin-anything-server' does not exist
Failed on delete user deepin-anything-server
dpkg: error processing package deepin-anything-server (--remove):
 installed deepin-anything-server package post-removal script subprocess returned error exit status 1
dpkg: too many errors, stopping
Errors were encountered while processing:
 deepin-anything-server
Processing was halted because there were too many errors.
E: Sub-process /usr/bin/dpkg returned an error code (1)

Other information: OS : Ubuntu Studio

Are there any workaround for this? or solution? Thanks!

Edit: Result of apt-cache policy deepin-anything-server

  Installed: (none)
  Candidate: 5.0.1-4
  Version table:
     5.0.1-4 500
        500 http://ppa.launchpad.net/ubuntudde-dev/stable/ubuntu focal/main amd64 Packages
        100 /var/lib/dpkg/status 

You have to use a trick - create needed user, remove package, then remove user:

sudo useradd deepin-anything-server
sudo apt-get purge deepin-anything-server
sudo userdel deepin-anything-server

and then for other DKMS-related package

sudo apt-get purge deepin-anything-dkms
sudo dpkg -P --force-all deepin-anything-dkms

Then update package lists and fix package system:

sudo apt-get update
sudo apt-get install -f

If you want to remove Ubuntu DDE stable PPA - remove it with its packages by

sudo apt-get install ppa-purge
sudo ppa-purge ppa:ubuntudde-dev/stable