eague/oauth2-server is not compatible with plugin?

[mawe777]

Hi, it is really not easy to become working. What I did is:

• nextcloud and suitecrm are accessible at https://
• create in directory Api/V8/OAuth2/ private.key + public.key
• sudo -u www-data composer install
• sudo -u www-data composer require lcobucci/jwt
• sudo -u www-data composer require league/oauth2-server
• add 'allow_local_remote_servers' => true, to nextcloud configuration
• add AllowOverride All / Options ... / Require ... to apache-config
• "Repair" in SuiteCRM the .htaccess file
• create OAuth2 - Token
• add ID and secret in "Admin"-Configuration at nextcloud after installing plugin
• add username + password for local user (tested with admin and new created user) but it always show me errors in logfile.

apache error log AH01071: Got error 'PHP message: PHP Fatal error: Declaration of Api\V8\OAuth2\Repository\ClientRepository::getClientEntity($clientIdentifier, $grantType, $clientSecret = NULL, $mustValidateSecret = true) must be compatible with League\OAuth2\Server\Repositories\ClientRepositoryInterface::getClientEntity($clientIdentifier) in /var/www/html/crm8/public/legacy/Api/V8/OAuth2/Repository/ClientRepository.php on line 33'

apache access log "POST /Api/access_token HTTP/1.1" 500 5600 "-" "Nextcloud SuiteCRM integration"

I tryed a lot of times, searched the internet, but no success. I hope there is an answer for me what I miss to do.