Contract REST returns: You must enter a valid value for the Business Unit attribute. (OKC-195787)

Hi All,

I want to create a contract via REST API /fscmRestApi/resources/11.13.18.05/contracts,

but it returns:

You must enter a valid value for the Business Unit attribute. (OKC-195787)

After I changed it to another Business Unit, API works.

I am sure the original BU existed in system and it's a function BU.

May I know why?

Thanks in advance！

Weitao