USPS Unable to connect issue

-- HikaShop version -- : 2.3.2
-- Joomla version -- : 2.5.24
-- PHP version -- : 5.3.28
-- Browser(s) name and version -- : FIREFOX 31.0
-- Error-message(debug-mod must be tuned on) -- : USPS error: 80040b1a Authorization failure. Perhaps username and/or password is incorrect.
Failed to obtain shipping quotes.
USPS error: 80040b1a Authorization failure. Perhaps username and/or password is incorrect.
Failed to obtain shipping quotes.
No payment methods found
No shipping method found

We are getting this error when using our login name and password. However, on the actual USPS site, we can log in fine using the same credentials.
We cannot find a reason why this is happening and no other errors are showing. USPS documentation and help don't help.
What do you recommend we do to track down the issue and fix it?

I'm having the a similar issue as well.

-- HikaShop version -- : 2.3.2
-- Joomla version -- : 2.5.24
-- PHP version -- : 5.4.30
-- Error-message (USPS error: 80040b1a Authorization failure. You are not authorized to connect to this server.
Failed to obtain shipping quotes.