Creating subscription by API request fails with error status, however subscription created with no hosting

For the first issue change the username testusername123456 according to the following requirements:

It is possible to use lowercase alphanumeric, dash, and underscore symbols in the username. The username should start with a lowercase alphabetic character and should be between 1 and 16 characters in length.

For example, the username testusername123456 consists of 18 characters, while the maximum characters for a username are limited 16. To solve the issue for this case, it is needed to remove 2 characters.

For the second issue, as a workaround, manually remove the partly created subscription in Plesk and then recreate it via WHMCS.

• Connect to the server using SSH.

• Check the file /etc/passwd if the user from the error exists there and delete all found lines:

  # grep testuser /etc/passwd
  testuser:x:10340:1003::/var/www/vhosts/example.com:/bin/false

• Create Plesk database backup

• Access Plesk database and remove all orphaned records from the Plesk database according to the following example:

  # plesk db
  mysql> select * from sys_users where login like "%testuser%";
  +-----+---------------+-----------------+------------+-------------------------------+------------+-------+-----------+
  | id | serviceNodeId | login | account_id | home | shell | quota | mapped_to |
  +-----+---------------+-----------------+------------+-------------------------------+------------+-------+-----------+
  | 411 | 1 | testuser | 2690 | /var/www/vhosts/example.com | /bin/false | 0 | NULL |
  | 416 | 1 | testuser | 2702 | /var/www/vhosts/example.com | /bin/false | 0 | NULL |
  +-----+---------------+-----------------+------------+-------------------------------+------------+-------+-----------+
  
  mysql> select * from web_users where sys_user_id=411 OR sys_user_id=416;
  Empty set (0.00 sec)
  mysql> select * from ftp_users where sys_user_id=411 OR sys_user_id=416;
  Empty set (0.00 sec)
  mysql> select * from hosting where sys_user_id=411 OR sys_user_id=416;
  Empty set (0.00 sec)
  mysql> select * from ScheduledTasks where sysUserId=411 OR sysUserId=416;
  Empty set (0.00 sec)
  mysql> select * from subdomains where sys_user_id=411 OR sys_user_id=416;
  Empty set (0.00 sec)
  mysql> select * from accounts where id=2690 OR id=2702;
  +------+------+----------------------------------------------------------------+
  | id | type | password |
  +------+------+----------------------------------------------------------------+
  | 2690 | sym | $AES-128-CBC$Q1AgXs3iTyjYsDpBFeOvRw==$OCZVaOCBMWG2+dQ2uDOeRQ== |
  | 2702 | sym | $AES-128-CBC$+vbXTORYdJuoWO7s4jXyLA==$f39OnbhjobEtY/I+i0ypMQ== |
  +------+------+----------------------------------------------------------------+
  2 rows in set (0.00 sec)
  mysql> delete from accounts where id=2690 OR id=2702;
  Query OK, 2 rows affected (0.00 sec)
  mysql> delete from sys_users where id=411 OR id=416;
  Query OK, 2 rows affected (0.00 sec)