When users logout, you can revoke the access_token and refresh_token which your application received in order to prevent any future use.
If your Realm's access_token_retention_policy is set to no-store, revoking an access_token is a no-op, and the access_token will be usable until it expires

Revocation Request

POST /token_endpoint HTTP/1.1
Host: oauth.server
Content-Type: application/x-www-form-urlencoded
token=AN_ACCESS_OR_REFRESH_TOKEN_VALUE
&client_id=YOUR_CLIENT_ID
&client_secret=YOUR_CLIENT_SECRET

Revocation Response

The revocation_endpoint will only return errors if
  1. The Realm used does not exist
  2. The client_id does not exist
  3. The client_secret does not match for the client_id.
For all other scenarios a 200 Ok will be returned, even in case the client_id provided does not own the token passed
HTTP/1.1 200 Ok