VAT issue in Intercompany billing

Dear All,

My case, sending stocks from country DE to AT, DE plant belongs to NL company code. while in F2 invoice its picking ship to country is AT correctly, but when we do Intercomapny billing system picks ship to as AT customer but country SIS tax is picking DE and VAT number is picking DE VAT number, here we want to be AT. and payers VAT number.

Please let me know if you not understand.