Hi Mario,
They are not so obvious questions. It took me sometime to know how to use this BAPI and I'm still learning. Some fields are not easy to complete. Try to post with FB01 and then replicate your document with the BAPI
I made this example
DOCUMENTHEADER:
USERNAME: my_user
HEADER_TXT: TEXT-01
COMP_CODE: your_company
DOC_DATE: document_date
PSTNG_DATE. posting_date
DOC_TYPE: document_type
ACCOUNTGL:
ITEMNO_ACC: 00000010
GL_ACCOUNT: expense_account
COMP_CODE: your_company
TAX_CODE: vat 21 %
COSTCENTER: cost_:center
ACCOUNTPAYABLE:
ITEMNO_ACC: 000000020
VENDOR_NO: vendor_number
PMNTTRMS: payment_terms
BLINE_DATE: baseline_date
ACCOUNTTAX:
ITEMNO_ACC: 00000030
GL_ACCOUNT: tax_account
TAX_CODE: vat 21%
CURRENCYAMOUNT:
ITEMNO_ACC: 00000010
CURR_TYPE: 00 (Doc currency)
CURRENCY: USD (foreign currency)
AMT_DOCCUR: 1000,00
EXCH_RATE. 10
ITEMNO_ACC: 00000020
CURR_TYPE: 00
AMT_DOCCUR: 1210,00- (look "-" sign)
CURRENCY. USD
EXCH_RATE. 10
ITEMNO_ACC: 00000030
CURR_TYPE: 00
AMT_DOCCUR; 210,00
CURRENCY: USD
EXCH_RATE: 10
AMT_BASE: 1000,00
Check for RETURN table for errors. You can complete all fields, but these should create a Vendor invoice.
Kind Regards