Well, I must have simply misspoke.
I tried to upgrade version from 6.3.2 to 7.2.0.
I did not want it and had an error with Kibana (kibana.yml I had the elasticsearch.url instead of elasticsearch.hosts).
So I tried to came back to previous version 6.3.2 but I got the error I pasted.
Denis Lamanov told me that it is forbidden to downgrade from 6.8, so I just keep the 7.2.0 version aand resolve the kibana.yml issue.
Hope I be clear this time.