The following error message occurs during an attempt to create a subscription or access to existing subscription settings:
ERROR: Call to undefined method PHosting_Apache::getPHPIni() (Apache.php:882)
It is not possible to install Wordpress via
Application Vault for domain
ERROR: Call to undefined method PHosting_Apache::getPHPCliPath() (Adapter.php:134)
Exact root cause is not clear. Looks like MUs were not installed during Plesk deployment.
Run autoinstaller and update all the packages:
# plesk installer --select-release-current --upgrade-installed-components