How to establish a connection between HoloLens and a MQTT broker? - mqtt

I'm very new to HoloLens development. Therefore please excuse me if this is an amateur question. I'm currently working transmitting hand gestures detections of the HoloLens to an external MQTT broker.
My use-case it, when I detect a hand tap(from HoloLens), I need to send(publish) a message to a subscribed topic in an MQTT broker.
I found this example on GitHub (https://github.com/gpvigano/M2MqttUnity). This publishes the message yet do not receive any messages. I'm getting the following error.
Connected to iot.eclipse.org:1883...
(Filename: C:\buildslave\unity\build\artifacts/generated/Metro/runtime/DebugBindings.gen.cpp Line: 51)
Test message published
(Filename: C:\buildslave\unity\build\artifacts/generated/Metro/runtime/DebugBindings.gen.cpp Line: 51)
'M2MqttUnity.exe' (CoreCLR: CoreCLR_UWP_Domain): Loaded 'C:\Data\Users\DefaultAccount\AppData\Local\DevelopmentFiles\M2MqttUnityVS.Release_x86.per287\System.Diagnostics.StackTrace.dll'. Cannot find or open the PDB file.
Exception thrown: 'System.InvalidOperationException' in Assembly-CSharp.dll
Exception thrown: 'uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException' in Assembly-CSharp.dll
Exception thrown: 'System.AggregateException' in System.Private.CoreLib.ni.dll
The thread 0x13b8 has exited with code 0 (0x0).
The thread 0xfdc has exited with code 0 (0x0).
The thread 0x700 has exited with code 0 (0x0).
The thread 0x179c has exited with code 0 (0x0).
Exception thrown: 'uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException' in Assembly-CSharp.dll
Failed to connect to iot.eclipse.org:1883:
uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException: Exception of type 'uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException' was thrown.
at uPLibrary.Networking.M2Mqtt.MqttClient.SendReceive(Byte[] msgBytes, Int32 timeout)
at uPLibrary.Networking.M2Mqtt.MqttClient.SendReceive(MqttMsgBase msg, Int32 timeout)
at uPLibrary.Networking.M2Mqtt.MqttClient.Connect(String clientId, String username, String password, Boolean willRetain, Byte willQosLevel, Boolean willFlag, String willTopic, String willMessage, Boolean cleanSession, UInt16 keepAlivePeriod)
at M2MqttUnity.M2MqttUnityClient.d__38.MoveNext()
(Filename: C:\buildslave\unity\build\artifacts/generated/Metro/runtime/DebugBindings.gen.cpp Line: 51)
Anyone tried this before repository before or any idea about what this error is?

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]
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