UPS OAuth Authentication Issue

-- url of the page with the problem -- : grandprix-software-central.com/index.php/shopping
-- HikaShop version -- : 6.1.0
-- Joomla version -- : 5.3.3
-- PHP version -- : 8.2.29
-- Browser(s) name and version -- : Firefox 142.0.1
-- Error-message(debug-mod must be tuned on) -- : An error occurred. The connection to the UPS server could not be established.
250002 Invalid Authentication Information.

I am trying to add UPS shipping with the newer plugin, as the old plugin no longer works. I've created a new account with UPS and added an app. I have Client ID, Client Secret, UPS account number, name, and address entered into the plugin.

I tried doing a web search on the error and came up with this webpage, which was a bit helpful:

https://octolize.com/docs/article/ups-labels-how-to-get-api-connection/#client-credentials

I added the ‘Authorization (OAuth)’ ‘Rating’, ‘Address Validation’, ‘Locator’, and 'Shipping' api's but am still getting the authentication error. I try my credentials in their demo plugin and they are accepted.