This happens in environment NET 8.0 + iOS + MAUI.
Running the same app (NET 8.0+MAUI) in Windows works fine.
Whether the problem is with Microsoft’s iOS MS.NET implementation or OpenAI’s use of unsupported (on iOS) API instead of some other API I do not know.
The docs say the MS.NET client library supports NET 6.0 only but then it should not work on Windows+NET 8 either if we are being obtuse.
Workarounds are welcome!