Well when you run Fiddler on the system where your app runs do you see the traffic from your app in Fiddler? If not then you will have to set Fiddler to be the proxy of your app (127.0.0.1:8888). On start Fiddler sets itself as the WinINET proxy but your app might not respect these settings or use a different network API so the proxy setting is really app dependent.
On a side note there is no TLS 2.X. The latest version is 1.2. Hopefully you got the version number wrong but it might be the case that you are trying to do something completely different so please double check the stuff on your side.
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