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- Manually deleting the folder in the cache (i.e. delete the folder that has the assetid of the asset that should be deleted).Call the following endpoint in Sitecore: http(s)://<sitecore url>/damforsitecore/mediacache/assetactions/<assetid>, which will also delete the cacheentry for the given assetid.
- Use the Administration DAM for Sitecore it has a function called Image cache where you can delete the cache from UI. DFS 9.2.0 - Administration dashboard