About Elastic Cluster status erro

Elasticsearch version is 7.3.1.
Due to the frequent data cleaning of the index in the early morning, memory fusions occur frequently in multiple nodes. At this time, another index is performing a bulk operation, and the written index will be unavailable. After exceeding the maximum number of retries since the recovery of the index by 5, the file information of the index is all empty. When writing to this index, report no such shard, However, the cluster status is green, which I think is unreasonable.

Welcome to our community! :smiley:

You will need to provide a bit more technical information and clarification please.
What is this data cleaning?
What does the bulk do, how large is it?
What happens when the index becomes unavailable?
What is in your Elasticsearch logs?
What is the output from the _cluster/stats?pretty&human API?

Please upgrade, that version is long past EOL.