I did this and now it is enrolled, topic can be closed
rm /etc/systemd/system/elastic-agent.service
root@elk:/opt/Elastic# rm -r Agent
curl -L -O https://artifacts.elastic.co/downloads/beats/elastic-agent/elastic-agent-8.11.2-linux-x86_64.tar.gz
tar xzvf elastic-agent-8.11.2-linux-x86_64.tar.gz
cd elastic-agent-8.11.2-linux-x86_64
sudo ./elastic-agent install --url=https://:8220
--fleet-server-es=https://localhost:9200
--fleet-server-service-token=
--fleet-server-policy=fleet-server-policy
--certificate-authorities=/etc/elasticsearch/certs/new/ca.pem
--fleet-server-es-ca=/etc/elasticsearch/certs/new/ca.pem
--fleet-server-cert=/etc/elasticsearch/certs/new/elasticsearch.crt
--fleet-server-cert-key=/etc/elasticsearch/certs/new/elasticsearch.key
--fleet-server-port=8220
thanks