Went into ulster bank today to pay off some of the mortgage. I gave them my mortgage reference number and they said that wasn't right. I have used this before and it was fine. They said they need the mortgage account no so I gave them the iban of my mortgage where I see the balance on their app.They said this wasn't right either. Can anyone tell me account number they want? An account was set up that me and the wife pay into and its taken out of that. Would this be what they're looking for or do I need to inquire with the mortgage crowd in Dublin?