I don’t think I can create HAR files on an iphone. The iphones are iOS 12, but I also heard that iOS 11 has the same problem.
I can however provide you with some server logs that show the continuous requests.
I’m not using an SDK specifically. Instead, I have followed the tutorials from Auth0 ASP.NET Core MVC SDK Quickstarts: Login (the app runs in a .net core 2.0 environment and another copy runs in .net core 2.1)
Edit:
my configuration is similar to this: Nginx Ssl and Auth0 goes into login loop