Fail to install dd-agent

[ghost]

olegs@neotrantor-ovm:$ uname -a
Linux neotrantor-ovm 4.4.0-124-generic #14814.04.1-Ubuntu SMP Thu May 3 07:26:53 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

olegs@neotrantor-ovm:~$ ps aux | grep dd-agent
olegs 24185 0.0 0.0 17184 2252 pts/37 S+ 15:45 0:00 grep --color=auto dd-agent

olegs@neotrantor-ovm:~$ sudo apt-get install datadog-agent
Reading package lists... Done
Building dependency tree
Reading state information... Done
datadog-agent is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] Y
Setting up datadog-agent (1:6.2.1-1) ...
Enabling service datadog-agent
Failed to issue method call: No such file or directory
dpkg: error processing package datadog-agent (--configure):
subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
datadog-agent
E: Sub-process /usr/bin/dpkg returned an error code (1)

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olegs@neotrantor-ovm:~$ sudo apt-get purge datadog-agent
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
datadog-agent*
0 upgraded, 0 newly installed, 1 to remove and 1 not upgraded.
1 not fully installed or removed.
After this operation, 324 MB disk space will be freed.
Do you want to continue? [Y/n] Y
(Reading database ... 303865 files and directories currently installed.)
Removing datadog-agent (1:6.2.1-1) ...
Failed to issue method call: Unit datadog-agent-process.service not loaded.
Failed to issue method call: Unit datadog-agent-trace.service not loaded.
Failed to issue method call: Unit datadog-agent.service not loaded.
Failed to issue method call: No such file or directory
Failed to issue method call: No such file or directory
Failed to issue method call: No such file or directory
find: `/opt/datadog-agent/agent': No such file or directory
Unable to delete .pyc files in /opt/datadog-agent/agent
Purging configuration files for datadog-agent (1:6.2.1-1) ...
Deleting dd-agent user
Deleting dd-agent group
Force-deleting /opt/datadog-agent
Processing triggers for ureadahead (0.100.0-16) ...

olegs@neotrantor-ovm:~$ sudo apt-get install datadog-agent
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
datadog-agent
0 upgraded, 1 newly installed, 0 to remove and 1 not upgraded.
Need to get 0 B/93.7 MB of archives.
After this operation, 324 MB of additional disk space will be used.
Selecting previously unselected package datadog-agent.
(Reading database ... 293812 files and directories currently installed.)
Preparing to unpack .../datadog-agent_1%3a6.2.1-1_amd64.deb ...
Unpacking datadog-agent (1:6.2.1-1) ...
Processing triggers for ureadahead (0.100.0-16) ...
Setting up datadog-agent (1:6.2.1-1) ...
Creating dd-agent group
Creating dd-agent user
Enabling service datadog-agent
Failed to issue method call: No such file or directory
dpkg: error processing package datadog-agent (--configure):
subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
datadog-agent
E: Sub-process /usr/bin/dpkg returned an error code (1)