Elasticsearch index corruption

Hi Team ,

Myself selvam,
we are having lacs and tons of data in elasticsearch clusters,
The problem is we are having mapping collusion issue.
due to this elasticsearch shards are corrupted. we need to revert back the cluster to old snapshot between that time customer facing issue..
Can you Please help on this.........

myself checked the migration plugin we have more than 1000 mapping lot and lot of fields collapsed with other fileds..... cann't able to revisit all the mappings...

give me suggestion what is the best way to solve this mapping collusion issue.