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Check if a security application is running on the agent machine and turn it off and test connectivity.
Review if your company has installed a security application like Windows Defender that can refuse the communication. If that is the case, please turn it off and try again.
If the situation continues now check your company's firewall security devices to ensure the traffic is identified and available.
Step 5 - Is Agent behind a load balancer
Is the agent behind a load balancer? If that's the case, Ask the IT to configure a sticky session in the load balancer of the agent and try again.