i want to make form for opening bank account. I'm thinking about asking the user first if they have already an account in that bank, and then ask them their account number. After they filled it, the system will detect in two different ways. If the user is a customer, system will give them a simple form to be fill. But if they don't have, they will got a long form and must filled all of the field.
Now i'm concern about the journey, will user end up abandon the form because i ask them their bank account number first or no? :/
One more question, if the user is customer. Should i make the form with prefilled field (All field will show up, but user cant edit it) or i just give them a simple form(User cant see what is being prefilled, but the form appearances will be likely more simple)