Fund in FM - K_COSTS_PLAN_INTERFACE_PERIOD set to 400 always

Hi Experts,

We are using standard FM K_COSTS_PLAN_INTERFACE_PERIOD with below data posted to it

Here we are passing Fund = 536. After creating the document number, if we see in the transaction CJI4 for the created document number we are seeing Fund always as '400' instead of Fund - 536. This is happening always. I debugged the standard FM but could see the value of Fund 536 is changed to 400.

Could you please suggest if any idea or any notes to applied.

output looks like below.

Regards,

Rafi