iOS Credential Provider Extension Not Offered When Creating Passkeys

I'm developing an iOS app that contains a Credential Provider Extension, and I want it to support passkeys. I've set the ProvidesPasskeys key to YES in the Info.plist of the extension, and in the CredentialProviderViewController I've implemented:

func prepareCredentialList(
    for serviceIdentifiers: [ASCredentialServiceIdentifier]
)

func provideCredentialWithoutUserInteraction(
    for credentialRequest: ASCredentialRequest
)

func prepareInterfaceToProvideCredential(
    for credentialRequest: ASCredentialRequest
)

func prepareInterface(
    forPasskeyRegistration registrationRequest: ASCredentialRequest
)

Standard password autofill suggestions that I have added to the system store are presented to me when I arrive to the corresponding login page, and the autofill flow succeeds via my extension. When I attempt to create a new passkey on my iPhone, whether it be in Safari on a website that supports passkeys (e.g. google.com) or within a native app that supports the creation of passkeys (e.g. PayPal), I am not given the option to create a passkey using my extension. The only option that is provided to me is the builtin Keychain option. On the "Settings->Passwords->Password Options" page I have "AutoFill Passwords and Passkeys" switch on and in the section titled "USE PASSWORDS AND PASSKEYS FROM:". I have selected both my app and "iCloud Passwords & Keychain". If I uncheck "iCloud Passwords & Keychain" and then attempt to create a passkey then I am shown a system sheet which tells me to go to the settings page to "choose how to manage passkeys".

Any ideas on how to troubleshoot this situation?

Thanks very much!

-Jeremy