Cannot create or migrate Plesk domain: The user already exists

Symptoms

1. Cannot migrate or create subscription:

   WARNING: (Restore domain object ‘example.com’)
   Execution of /opt/psa/admin/plib/api-cli/domain.php –update example.com -guid 2f0a7ad4-7003-4a81-8f2d-faaefaa6ad77 -creation-date 2016-11-09 -description ” -hosting true -hst_type phys -do-not-apply-skeleton -ip 203.0.113.2 -www-root httpdocs -login user -passwd '' -passwd_type sym -ignore-nonexistent-options failed with return code 1.
Stderr is
An error occurred during domain update: An error occurred during changing of hosting settings: The user john.doe already exists.

2. There is no record about the user in
psa
database:

   MYSQL_LIN: select * from sys_users where login = ‘john.doe’;
   Empty set (0.00 sec)

3. Error when creating a subscription via command line:

   # plesk bin subscription -c example.com -owner admin -service-plan “Default Domain” -ip 203.0.113.2 -login john.doe -passwd “”
   An error occurred during domain creation: An error occurred during changing of hosting settings: The user john.doe already exists.

Cause

The user already exists in the system.

Resolution

1. Login to Plesk via SSH
2. Delete the user from the system and move his home directory:

   # less /etc/passwd | grep john.doe
   john.doe:x:10006:1004::/var/www/vhosts/example.com:/bin/false
   # userdel john.doe
   # mv /var/www/vhosts/example.com ~/