Failed to rebuild elastic index

Hi @fliebe92 ! I have several identical errors, for different tickets.
Here is an example of one of them:
[12:14:56.006764#283501-6300] ERROR – : Unable to send Ticket.find(5259).search_index_update_backend backend: #<RuntimeError: Unable to process post request to elasticsearch URL ‘http://localhost:9200/tickets_zammad_production_ticket/_doc/5259?pipeline=zammadcb54f5b7-3b9d-4339-9760-e429c93fb762’