Oauth grant_type error, postman

Google Cloud Apigee
4

It seems to work when I add request.queryparam.grant_type:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>

OA-GenerateAccess GenerateAccessToken

1800000

client_credentials

request.queryparam.grant_type

Not sure why it doesn’t work when I specify it as a grant type in the proxy.

Thank you.