Many funds in an Interest Rate Instrument

Hello,

I activated the business function FIN_TRM_PSM_INTEGRATION

Then I created an operation Interest Rate Instrument I assigned a Fund.

In the first due date the fund changed from 55828SA143 to 5828SA143

I used the transaction TPM80 and I changed the fund successfully.

Then in the second due date the fund in now 5828SA143   but they need to assign 50% to the fund 5828SA143 and the other 50% to the fund 5828SA141. This operation is exclusive for this due date, because,

In the third due date we need to pay 100% in the fund 5828SA143 (as same as the first due date)

Someone know how to change the fund for each due date?

Best regards

Adriana Rivera