Oracle Payables - APXIIMPT - Invalid Sequence rejections

Question

Hello Guys:
My Business users are complaining that they are getting lot of rejections while running APXIIMPT ( Payable Open Interface Report for Invoices) due to invalid sequence error. We logged a TAR with oracle and I am not getting any where after this. The support tech expects me to work with her as a functional consultant but I am not. I am pasting the response from the Support tech.
Can any one give me more details on How to check this? I would really appreciate it.
We are using Standard Invoice - STDINV
The first statement says we need to check the document category code, but she never explains how to check this. I looked at the Oracle payables guide and it is completely text no diagrams.
Regards,
Bala
UPDATE
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I gave you step by step on how to check the document catergory code that you are using for the invoice above.
The rejection you are receiving is usually because you have not setup the document catergory code correctly
Just replace the create with the name of the sequence you already have set up and
check to see if it is setup as the above.
For example:
1. Application>Document>Define (query on sequence you are using for the invoice)
A sequence can be Manual or Automatic.
If it is Automatic an Oracle Sequence Object will be created starting
at the designated beginning number and that sequence will be used to
generate the document numbers. After a record in this form is
saved, and type = Automatic, a Concurrent Process is submitted to create
the Oracle Sequence.
2. Examine Document Categories
Application>Document> query on Categories assigned to sequence above
There are numerous document categories already defined for Oracle Payables.
The default category used in creating Voucher numbers for Payables Invoices
in the Invoice Workbench is STD INV.
If the Payables "Option Allow Document Category Override" in the
Invoice region is checked, the Document Category can be changed to any category
that has a Table Name of AP_INVOICES_ALL.
3. Assign Document Sequence to a Category.
Application>Document>query on Assign
In the Documents Region, indicate the application, the document category,
the set of books, and the method of entering the sequence number.
The method is Automatic, Manual, or Null.
THIS IS THE MOST COMMON SOURCE OF ERROR.
The method is used to tell the system how the record is being created:
a. Manual means that the record is being created by a form such
as the Invoice Workbench.
b. Automatic means the record is being created by a Concurrent
Process such as Invoice Import.
Setting the assignment as Automatic, will result in an error when
trying to enter an invoice using the Invoice Workbench.

Answer 1

For whatever it is worth....
This is resolved by ledger set up--> Accounting Setups and adding the balancing segments for which the accounts relate to.