updating bank details in transaction BP

We're implementing S4 HANA and we have a program that updates Business Partners in transaction BP. I'm trying to get this to update the bank details under the 'Payment Transactions' tab but so far I haven't been able to find a standard function module that will update this.

FM 'BAPI_BUPA_BANKDETAIL_CHANGE' seems to update the account details in LFBK but not the table underlying the data in the 'Payment Transactions' tab. I've also tried 'BUPA_BANKDETAILS_CHANGE' but this doesn't work either - I get no errors but my account details aren't updated (yes I am committing afterwards).

Can anyone offer any advice on this please?

Thanks,

Malcolm.