I need to replace a lost/stolen ILR BRP and so does my four-year-old daughter—both were taken at the same time

Could anyone advise about this and how I can fix it so as to book a biometrics appointment for my daughter? I received the email about IDV app and the possibility of using that, so I can't book for myself yet, but I don't think my daughter will be eligible to use the app.
Thanks in advance,
Hannah