.NET Core 7 Global Exception Handling Middleware Requires Refresh!

Thank you in advance to anyone who can assist- I have a .NET Core 7 Blazor app and I have instituted GEH via a middleware class that catches the next request via RequestDelegate and inserts into a try/catch block (see attached image); The problem is that, while it works, the page has to be refreshed in order for the custom message/problem to be shown. Is this an issue with the RequestDelegate? That it only executes after the current response?