Hello @yassk ,
With a quick review of the connection details utilized here, it looks like we are using port 8884. Typically, this is the port configured for HiveMQ Cloud brokers for WebSocket connections, rather than traditional client TCP connections. Additionally, is this connection request also submitting an MQTT connection, or is this request just initiating a TCP connection to the provided address? In order to submit MQTT messages, both a TCP connection and the submission of an MQTT connection packet is required. More specifics on MQTT connectivity can be found in our essentials series, here.
Please verify if a connection via port 8883, and a submission of a connect packet, then publish requests offer proper MQTT traffic. Please note that HiveMQ Cloud brokers require a TLS connection, as well. Some devices may require a server CA cert in order to establish connectivity, and that can be found on our FAQ page here in the community forum. Additionally, if you have further questions or encounter additional roadblocks, please share as much of the TCP connection, MQTT connection, and publish code blocks as possible, obfuscating any private information, so we can diagnose further.
Best,
Aaron from the HiveMQ Team