MQRC_Q_MGR_NOT_AVAILABLE error on windows

I have an ASP .NET core 3.1 application running on Windows server.

When I try to connect to MQ I get the error 'MQRC_Q_MGR_NOT_AVAILABLE'.

Please find the code as below:

            string cipherSpec = "TLS_RSA_WITH_AES_128_CBC_SHA256";
            string cipherSuite = "SSL_RSA_WITH_AES_128_CBC_SHA256";

            queueProperties.Add(MQC.HOST_NAME_PROPERTY, strHostName);
            queueProperties.Add(MQC.PORT_PROPERTY, port);
            queueProperties.Add(MQC.CHANNEL_PROPERTY, strChannelName);
            queueProperties.Add(MQC.TRANSPORT_PROPERTY, MQC.TRANSPORT_MQSERIES_MANAGED);
            queueProperties.Add(MQC.SSL_CERT_STORE_PROPERTY, "*USER");
            queueProperties.Add(MQC.SSL_CIPHER_SUITE_PROPERTY, cipherSuite);
            queueProperties.Add(MQC.SSL_CIPHER_SPEC_PROPERTY, cipherSpec);

            try
            {
                MQQueueManager _queueManager = new (queueManagerName, 
            queueProperties);
                _queueManager.Connect();
            }
            catch (MQException exp)
            {
                _logger.LogInformation(" Connection Fail " + exp.Message);
            }