Plesk Repair Kit shows a warning: service plans with unregistered PHP handlers were found

Symptoms

• Plesk Repair Kit 'Web and FTP Servers' check shown the error:

  PLESK_ERROR: '1 service plans with unregistered PHP handlers were found.'

• The following is displayed in Tools & Settings > PHP Settings:
  

  PLESK_ERROR: Error:The following PHP version(s) are not installed: 7.3.33. Install them or run plesk bin php_handler --reread to update information about the registered PHP versions.

• The following command returns the error:

  # plesk repair web -php-handlers -v -n
  
  Checking the usage of PHP handlers
  
  The following service plans have unregistered PHP handlers: ....... [ERROR]
  - Admin Simple
  The issue could be resolved only in the interactive mode (without -y and -n options).
  
  Error messages: 1; Warnings: 0; Errors resolved: 0
  
  exit status 1

Cause

PHP handler was removed or missing.

Resolution

1. Log into Plesk
2. Follow steps from this article to change the PHP version for an affected service plan from Plesk UI