@Nagarjuna11 ,

Can you share how you configured the entity selection action?

@ylandovskyy 

I have set the action type to manual when im updating the hostname it is returning no matching entities found.

when i created the manualcase i added the entity as well but it is not picking up.

You should use the same setup as I've provided in this post:

https://www.googlecloudcommunity.com/gc/SecOps-SOAR/Mitigation-Actions-What-is-the-best-way-perform-mitigation-only/m-p/911109#M4169

@ylandovskyy I manually added an entity to the case, following the steps you outlined in the previous post. I selected the placeholder 'Entity.Identifier', but it returned 'No matching entities found.' Is there a different placeholder I should use for manually added entities? Please advise.

@Nagarjuna11 2 notes here:
- Entity.Identifier is always in upper case, so your matching value should be like that as well
- If you need to provide more than 1 entity, then you need to create multiple conditions with "OR" logic

As the value is not clear, I don't know exactly the issue, but was the value provided according to these 2 rules?

@ylandovskyy  I added the device ID in the Entity.Identifier field to execute the Defender AV scan, but since the device ID is in lowercase, it’s not being recognized. 

You need to provide the same value in Upper case and it will result in a match then (assuming you have that entity in the alert).

Tip: to check you have the right inputs that the server will understand:
Create a manual Case, add the entity manually, then run a manual Action, if it works you know the end goal for the playbook to achieve.  If you get the same error it suggests the 'Entity' is not in the right format (upper lower, comma separated, etc)