Hi,
From my point of view, this is more likely a connection issue rather than ssrs issue. In SSRS there is not such settings could affect like this . I found some trouble shoot direction that may be helpful.
This problem occurs when the server or another network device unexpectedly closes an existing Transmission Control Protocol (TCP) connection. This problem may occur when a time-out value on the server or on the network device is set too low. The problem can also occur if the server resets the connection unexpectedly, such as if an unhandled exception crashes the server process. Analyze the server logs to see if this may be the issue.
To resolve this problem, make sure that you are using the most recent version of the .NET Framework.
Best Regards,
Joy