Purchase Order - doc_date realtion with FISTL and FIPEX

[rerewjddn]

Dear. Experts.

Hello,

Firstly, I tried to change poaccount-cmmt_item and poaccount-funds_ctr using of fucntion 'BAPI_PO_CHANGE'.

but the changed values of two items are bring not what I expected. Actually its worked for other PO.

Secondly, I tried to create new PO in transaction code ME21N with same condition what I tried to change before.

but according to doc_date(creation date of PO) poaccount-cmmt_item and poaccount-funds_ctr brings different value..

ex)

doc_date = 2021.07.31

FISTL = 'Y9999'

FIPEX = '99999999'

doc_date = 2023.08.01

FISTL = the value what I want

FIPEX = the value what I want

Are there any soloution that can help me out..?

Best regards,

Warren.