Church Account is the primary user account (user name and password) for accessing online Church resources. Church Account was formerly known as LDS Account. This forum is a space to discuss all things related to Church Accounts (registration, account recovery, user experience, vulnerabilities, etc.).
You'll need to get the phone number of the Global Service Centre from your ward clerk. The Global Service Centre can reset the MFA settings on your account so you can set it up on your new phone.