Hi Phanindra,
End Date is available, out of the box. So, you don't need to add a new simple attribute L3 configuration. If you want to inactivate a profile from the UI, you can do the following
- Navigate to the base attribute facet on the profile in EDIT mode.
- Click on "More Attributes" and Select "End date".
- Update a value older than the current date in the "End date" field and that will inactivate the profile.

The same thing can be done using API as well. Here is a documentation for that - https://docs.reltio.com/en/explore/get-going-with-apis-and-rocs-utilities/reltio-rest-apis/model-apis/entities-api/update-entities/retrieve-or-modify-the-entity-startdate-and-enddate#change-enddate-0
Sample CURL command for retrieving and updating the end dates of an entity
curl --location 'https://{{env}}.reltio.com/reltio/api/{{mdmTenant}}/entities/{{entityId}}/activeness/endDate' \
--header 'Authorization: Bearer XXXXXXX' \
--header 'Content-Type: application/json'
API to update the end date for an entity
curl --location --request PUT 'https://{{env}}.reltio.com/reltio/api/{{mdmTenant}}/entities/{{entityId}}/activeness/endDate' \
--header 'Authorization: Bearer XXXXXXX' \
--header 'Content-Type: application/json' \
--data '{
"value": 1696668038000
}'
Here, you have to provide the value of the end date in UNIX epoch format.
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Diparnab Dey
Technical Consultant
Reltio
Kolkata, West Bengal
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