Oracle seeded bank API overwrote bank account number with masked bank account number

We used an Oracle seeded external bank account update API to update one of the attributes on a bank account additional detail. But while running this API the expectation was that in the database, we will just pass the existing data back to the database, including the new value for the attribute. However, the standard API, for some reason overwrote the bank account number field in the database with the masked bank account number, creating a number of issues down the road.

So my questions is, is this is an expected behavior because we have the bank account masking turned on? and in the future if we are running a script update to the bank account information, should we turn the masking off temporarily while running the process, then turn it back on?