Failed to config cluster neo4j v5

Hello,
I am trying to install neo4j clusters with 3 nodes following the link https://neo4j.com/docs/operations-manual/current/clustering/setup/deploy/ . Once I add the dbms.cluster.discovery.endpoints:5000=server01.example.com,server02.example.com:5000,server03.example.com:5000 in my neo4.conf , the neo5j nodes stops automatically and I have the following error in the logs : " Caused by: com. neo4j.causalclustering.seeding.FailedValidationException: The seed validation failed with response [RemoteSeedValidationResponse{status=FAILURE, remote=XXXX:6000}, RemoteSeedValidationResponse{status=FAILURE, remote=XXXX:6000}]" However the port 6000 is well opened

Thank you for your precious help!