Access number (used to have BNZ Accounts + Personal Internet Banking)

I used to have Accounts (have Personal Internet Banking) with BNZ (Accounts Closed). I want to Open a Transaction Account (With Internet Banking). Cannot do Open via online (RealMe) due to “You’ve already opened a BNZ account using RealMe. To view it, log in to Internet Banking. You’ll find your access number in the confirmation email we sent you”
I do not have the ‘Access Number’. this is to me deleting the email, throwing out the netguard.
How could I get the ‘Access Number’
Do I call Customer Service?
Do I go to a Branch?
Thanks