SAP Treasury Reverse Repo with Collateral Transfer

Hi Expert,

I try to capture a reverse repo with collateral transfer (product type 73A, transaction type 100 Reverse Repo ). I assumed this is consider as invest/purchase and do no need on hand position.

In creation of contract (FTR_CREATE), after entering Spot Purchase (1001) and Forward Sales (1002), I hit error "Per <bond end of term> a negative balance of <total spot + forward amount> <Currency> Nominal exits", error message no. TRQ0001.

Can anyone help why this message prompt ? is it this is a purchase and do not require nominal "

Thank you,

Oscar