Api for nextjs is giving me a without an `onChange` handler for what reason, I don’t know.

so I’ve been watching tutorial about nextAuthv5, and after finishing the tutorial, I created my own api named appointment and created a simple get method but when I run the code, I received HTML instead of a simple response. It works when I call it on my website(paste the url in google) , but when I tried to call it in my postmark i received an html. I think it affects after changing the middleware.