How to remove specific user from item level permission through Rest API using power automate

There is a REST endpoint to remove user permissions from list item.

Use this endpoint:

<siteUrl>/_api/web/lists/getbytitle('<listName>')/items(<ID>)/roleassignments/removeroleassignment(principalid=<userID>,roleDefId=1073741827)

Replace <userID> with the actual user ID.

Microsoft documentation: Users, groups, and roles REST API reference