Changed SAP password not working while resetting using BAPI

You are using the structure Password for resetting the password. It is of type “BAPIPWD” and comprises of a field which is again named as “BAPIPWD”

When you need to reset the password, you need to specify the correct field name instead of password.

JCO.Structure structPassword = userChangeInput.getStructure("PASSWORD");
sPassword.setValue(nPassword, "BAPIPWD");