Hello @Akbarali-4925,
Thank you for your question.
There is a topic with a problem similar to yours, I recommend that you consult it through the link below:
https://social.technet.microsoft.com/Forums/en-US/557f2257-993f-40aa-8483-c6ad54467bf3/adfs-and-web-application-proxy-error-the-underlying-connection-was-closed- an-unexpected-error?forum=sfbfr
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