The error we are getting is an error and error code '2' is being encountered. Does this confirm rights?

They have full rights (to our knowledge) since they are able to use the system to enter/post etc with the data. So there must be something else going on.

Will contact their IT on this rights issue.

We didn't send the data purposely since we ran into this issue. FWIW the data is 'clean'. At least according to the data integrity check.