check at isusernametaken function

		$this->userManager->callForAllUsers(function (IUser $user) use ($ipAddress, $isDryRun, $output, &$stats) {

			$username = $user->getUID();

			// Get user metadata from LDAP to obtain usernameWithoutDomain

			$userMetadata = $this->ldapConnectionService->getUserMetadata($username);

			$usernameWithoutDomain = $userMetadata['usernameWithoutDomain'] ?? $username;

			// Check if user is missing from common database

			// Strip legacy domain from username before checking in common DB

			$usernameWithoutDomain = $this->userService->stripLegacyDomainFromUsername($username);

			if ($this->userService->isUsernameTaken($usernameWithoutDomain)) {

				return; // Skip if already exists

			}

	private function getDefaultQuota() {

		return $this->config->getSystemValueInt('default_quota_in_megabytes', 1024);

	}

	/**

	 * Remove legacy domain from username if present

	 */

	public function stripLegacyDomainFromUsername(string $username): string {

		$legacyDomain = $this->config->getSystemValue('legacy_domain', '');

		return str_ireplace('@' . $legacyDomain, '', $username);

	}

}