Unable to test using Authorize.net sandbox

Hi,
I’ve been trying to test submitting an order form using an authorize.net sandbox account.

I’m using the Authorize.net test CC numbers and zip codes as shown on this page:
Testing Guide

and as recommended by Infusionsoft staff here: Testing Credit Cards in Infusionsoft Order Form - #3 by martinc

I’ve tried the integration in all three modes on the Infusionsoft side, and each time I get a red error message at the top of the order form after submitting
Simulator mode → This account has not been given the permission(s) required for this request. (123)
Test Mode → (TESTMODE) The merchant login ID or password is invalid or the account is inactive. (13)
Live Mode → The merchant login ID or password is invalid or the account is inactive. (13)

How should I proceed?

Thank you

I had the wrong configuration for the Authorize.net login ID.

To find this setting, you can go to authorize.net > account > settings > api credentials and keys