Can't add banking app to existing bank sign in - iPhone 12

My friend can sign in to her bank's website using 1Password. When she attempts to use the banking app she has to manually open the 1Password app and then copy and paste the bank password into the app.

Once she has done that I would expect that a message would come up on the app asking if she would like to have the banking app remembered in 1Password, but she does not get this.

Is there any suggested way to add the app to the existing web login for the bank? She is using an iPhone 12.

Thanks

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