@Taisia00 The supported Auth-Grant types in StandardOauth2AccessTokenProvider  are  User Password  Client Credentials  Refresh Token  Please update the grant-type option in the API request to the supported values .  Check the below doc for the valid properties/options and further information. ref doc :  https://nifi.apache.org/docs/nifi-docs/components/org.apache.nifi/nifi-oauth2-provider-nar/1.28.0/org.apache.nifi.oauth2.StandardOauth2AccessTokenProvider/index.html If the above suggestion helps in your requirements, please clink on "Accept as Solution" on this update.   ... View more