Please rephrase the question.  You can update that code in a 1/2 dozen ways, so your question doesn't make sense.

Apologies if my previous question wasn't clear.
As a newcomer to Sage 300, I'm currently facing difficulty in locating the "account number" property when adding a new vendor.
I've also attempted to set it using the REST API, but without success. I couldn't even fetch that data...
If there is a straightforward solution that I may have overlooked,
I would greatly appreciate your guidance.
Thank you.

Vendors don't have "account numbers".  They have Account sets, and Bank Codes.

If you are after the bank account number of the account your company will pay the supplier from then, once you have the Bank Code 'SEATAC' on your screenshot you would then look up the bank code in Bank Services Banks.

Just to be clear this is not the Bank account of the supplier.

There is no default location for this in Sage Accounts Payable. 

Other modules like Orchid EFT Processing hold the Bank account number of the supplier.

Hi, I am looking for same information to setup ETF information to Vendors via API. Is it possible to add/update it via API? If yes, can you please point me to the correct direction.

Or is it only handled via Orchid module. Can we integrate with Orchid Module via API?

Thanks

Orchid only.  No API.