Sign certificate via aws private CA

Question

I have my CA certificate and leaf certificate which was signed by CA. Leaf is used for communication. I would like to sign it via aws private CA using NET, but I can't figured out witch class I have to use.

I have the function RequestSign which takes certificate for signing. _arn is imported via constructor class and _client AmazonACMPCAClient as well.

public async Task RequestSign(X509Certificate2 certificate)
        {
            var request = new ImportCertificateAuthorityCertificateRequest()
            {
                CertificateAuthorityArn = _arn,
                Certificate = new MemoryStream(Encoding.ASCII.GetBytes(certificate.ExportCertificatePem())),
            };
            var response = await _client.ImportCertificateAuthorityCertificateAsync(request);
            Console.WriteLine(response.HttpStatusCode);
            
        }

When I try to execute this function I get "The basic constraints extension must specify that the certificate is for a CA." exception.

Official documentation says Imports a signed private CA certificate into Amazon Web Services Private CA. This action is used when you are using a chain of trust whose root is located outside Amazon Web Services Private CA. Before you can call this action, the following preparations must in place: