Hi Nattudurai,
As far as I understand, the Interpretation algorithm enable us to find separate outgoing payments. In this case check if you have selected the proper Interpretation algorithm in the following configuration path:
SPRO>Financial Accounting (New)>Bank Accounting>Business Transactions>Payment Transactions>Manual Bank Statement>Create and Assign Business Transactions
As far as I understand even if we remove the reference field from the Manual Bank Statement Variant, the system will still check for it because that is one of the field defined for clearing in the int alg.
Also check if Interpretation Algorithm 21 helps.
Thanks & Regards
Subhasish