different results across web/protal and our site (API)

Our site is integarted via API with easyship for some time now. We see consistent results for identical shipments across the easyship portal and our site - as expected.
At your (easyship's) suggestion I created and different new (easyship) account and changed the access key to the new account (on our test environment).

In testing with the new account we see inconsistent results for identical shipments across the easyship portal and our site. Results on our site (via API) are fewer and and lot more expensive.

Could that be because the new account is not funded yet?
Other reason?
The new account ID is CIL602749