Describe the bug
I implemented a ChatCompletion Kernel with some OpenAPI plugins. Solution is working with version 1.16.2 of Semantic Kernel but stopped working after upgrading Semantic Kernel to one of the versions 1.18.2, 1.19.0, 1.20.0.

This is the Exception I get

with the detailed stack trace

It seems this should be the line throwing the exception

Platform

• OS: Windows
• IDE: Visual Studio
• Language: C#
• Source: Semantic Kernel 1.18.2, 1.19.0, 1.20.0

Additional context
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@markwallace-microsoft @SergeyMenshykh