使用服务器密钥签署客户端证书时无法加载证书错误

我正在遵循 https://thrift.apache.org/test/keys 的指南，但是当我尝试使用 server.key 使用以下命令签署客户端证书时：

openssl x509 -req -days 3000 -in client.csr -CA CA.pem -CAkey server.key -set_serial 01 -out client.crt

我收到以下错误：

Signature ok
subject=C = AU, ST = Some-State, O = Internet Widgits Pty Ltd
unable to load certificate
13644:error:0909006C:PEM routines:get_name:no start line:crypto\pem\pem_lib.c:745:Expecting: TRUSTED CERTIFICATE

CA.pem 文件：

Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            02:9b:5f:55:60:5a:bf:5b:ff:5a:b4:a4:af:6f:da:b1:de:21:4e:ec
        Signature Algorithm: sha256WithRSAEncryption
        Issuer: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd
        Validity
            Not Before: Mar  5 08:02:13 2021 GMT
            Not After : May 22 08:02:13 2029 GMT
        Subject: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd
        Subject Public Key Info:
            Public Key Algorithm: rsaEncryption
                RSA Public-Key: (2048 bit)
                Modulus:
                    00:de:f6:78:f9:15:b0:ae:f7:f0:bf:2e:d1:f7:4f:
                    84:b5:ba:55:e7:36:c7:54:4e:df:d3:65:6b:22:d4:
                    .... missin values ....
                    6b:cc:15:81:88:fa:b1:75:00:f7:e5:e9:46:79:4a:
                    25:96:b5:c0:f8:15:46:c3:69:55:79:8a:09:1c:c2:
                    84:4d
                Exponent: 65537 (0x10001)
        X509v3 extensions:
            X509v3 Subject Key Identifier: 
                78:7B:B3:8A:F0:C0:DB:62:30:EA:E5:CD:5B:FD:5E:F9:C3:3D:8A:0B
            X509v3 Authority Key Identifier: 
                keyid:78:7B:B3:8A:F0:C0:DB:62:30:EA:E5:CD:5B:FD:5E:F9:C3:3D:8A:0B

            X509v3 Basic Constraints: critical
                CA:TRUE
    Signature Algorithm: sha256WithRSAEncryption
         0e:06:d3:24:ac:03:56:6a:6f:02:2a:67:cb:38:37:31:e5:9c:
         01:3d:41:09:0b:a7:9e:da:02:67:5f:ee:3b:58:03:c2:9d:2f:
         .... missin values ....
         cc:83:be:ee:29:b1:15:2b:b8:a0:9f:ef:29:5e:2b:3d:25:68:
         80:df:8f:cc:26:ce:56:92:8b:e4:6b:84:1b:09:07:11:66:b5:
         32:47:15:18
-----BEGIN CERTIFICATE-----
....data...
-----END CERTIFICATE-----

可能是什么问题？