If you do not use the app, or if you use a physical security key, the difference in 365 phone services is that outside of business hours, you will not be able to use the self-service options to check your account balance, view recent transactions, order a statement, or make payments to existing beneficiaries. In the future, you will need to be registered for the app to access these services outside business hours. However, you can still speak to an agent during business hours to manage your accounts.