Hi Vishal,
Firstly you have to maintain the WHT as the Derived flow of the Main Interest Flow so that same is reflected in the deal. 1 IMG setting and and BP level setting has to be done for this.
Then please create BOA as Business Partner and maintain WHT table for BOA.
Now in your deal when you can maintain the BP for each Flow Type (in your case the WHT flow ) by maintaining the Payment Detail in Payment Detail Tab for particular flow with direction and Bank and BP detail.
See the screens below:
Main BP is 30000000 (SBI in your case)
and then maintain BOA(BP5 here) as BP in the Interest Flow Type.
Let us know if it solved your Issue.
Cheers !!!
Aditiya
