Elasticsearch has deleted all my visualizations and indexes


today I wanted to continue working on my visualizations and already at the registration I was shown That I cannot select a Space. Then I restarted my machine and thought nothing else. Afterwards I could log in again in Kibana and had to realize that everything is deleted. I looked into the elasticsearch logs and saw that all my indexes were deleted tonight. Here is a small excerpt from the logs:

I can not explain why! I did nothing over the weekend. This is happening twice already. The next problem, now I want to upload my backups ->Management -> Saved Object -> import I get the following message: Sorry, there was an error
The file could not be processed.

Best regards

It looks like there was an index named hello created. Do you by any chance have your cluster exposed and accessible from the internet without any security enabled so taht someone could have accessed it?