Firebase Admin SDK .NET Core C# – Import users from another project success but user cannot authenticate [auth/wrong-password]

I’m importing user from an old Firebase project to another.
The import ends successfully with no errors but from the new application, user cannot authenticate with same credentials and the following error is returned:

[auth/wrong-password]: The password is invalid or the user does not have a password.

This is the code I’m using to migrate users:

private async Task<MigrationResult> MigrateUsers(AbstractFirebaseAuth authFrom, AbstractFirebaseAuth authTo, UserImportOptions options, string? pageToken = null, MigrationResult? result = null)
{
    result ??= new MigrationResult
    {
        Success = false,
        SuccessCount = 0,
        FailureCount = 0
    };
    
    try
    {
        /* DOCS
         * - GET PASSWORD HASH AND SALT: https://firebase.google.com/docs/auth/admin/manage-users?hl=en#password_hashes_of_listed_users
         */
        var usersToMigrate = await authFrom.ListUsersAsync(new ListUsersOptions
        {
            PageSize = 1000,
            PageToken = pageToken
        }).ReadPageAsync(1000);
    
        var users = usersToMigrate.Select(u => new ImportUserRecordArgs
        {
            Uid = u.Uid,
            PasswordHash = Encoding.ASCII.GetBytes(u.PasswordHash),
            PasswordSalt = Encoding.ASCII.GetBytes(u.PasswordSalt),
            Email = u.Email,
            EmailVerified = u.EmailVerified,
            PhoneNumber = u.PhoneNumber,
            DisplayName = u.DisplayName,
            PhotoUrl = u.PhotoUrl,
            Disabled = u.Disabled,
            CustomClaims = u.CustomClaims,
            UserProviders = u.ProviderData.Select(p => new UserProvider
            {
                Uid = p.Uid,
                DisplayName = p.DisplayName,
                PhotoUrl = p.PhotoUrl,
                Email = p.Email,
                ProviderId = p.ProviderId
            })
        });
    
        var importResult = await authTo.ImportUsersAsync(users, options);
    
        _logger.LogInformation($"{nameof(MigrateUsers)}: Successfully imported {importResult.SuccessCount} users");
    
        if (importResult.FailureCount > 0)
        {
            _logger.LogWarning($"{nameof(MigrateUsers)}: Failed to import {importResult.FailureCount} users");
            foreach (ErrorInfo indexedError in importResult.Errors)
                _logger.LogWarning($"{nameof(MigrateUsers)}: Failed to import user at index: {indexedError.Index} due to error: {indexedError.Reason}");
        }
    
        result.Success = true;
        result.SuccessCount += importResult.SuccessCount;
        result.FailureCount += importResult.FailureCount;
    
        if (!string.IsNullOrWhiteSpace(usersToMigrate.NextPageToken))
            return await MigrateUsers(authFrom, authTo, options, usersToMigrate.NextPageToken, result);
    
        return result;
    }
    catch (FirebaseAuthException ex)
    {
        _logger.LogWarning($"{nameof(MigrateUsers)}: {nameof(FirebaseAuthException)} | {ex.AuthErrorCode} | From tenant {(authFrom is TenantAwareFirebaseAuth ? (authFrom as TenantAwareFirebaseAuth)?.TenantId : "Default")} to tenant {(authTo is TenantAwareFirebaseAuth ? (authTo as TenantAwareFirebaseAuth)?.TenantId : "Default")}", ex);
    
        result.Success = false;
    
        return result;
    }
}

and this is the ImportUsersAsync option object:

var options = new UserImportOptions()
{
    Hash = hash
};

where hash is:

var hash = new Scrypt()
{
    Key = Encoding.ASCII.GetBytes("[base64_signer_key from the OLD project]"),
    SaltSeparator = Encoding.ASCII.GetBytes("salt separator from the OLD project"),
    Rounds = 8,
    MemoryCost = 14
}

From the documentation this code should be fine and when the user opens up the new app, all they need to do is sign in again and the password should be rehashed and everything should works fine. But this is not happening.

What am I doing wrong?

Thank you!