Account determination : house Bank or house bank account was not entered

Dear Experts,

I am faced with following problem:

When trying to post the repayment flow (Update type SAM1104) for treasuty bills I get the following error :

""Account determination : house Bank or house bank account was not entered""

When checking the account assignment and the house banks entered in my deal, it should derive it in a correct way, but this does not happen. When entering dummy account for account symbol 3, it works. The systeem seems to have difficulties finding the correct account.

Any help?

kr,

Stef