Hey Roy, Kevin here, Make sure you paste the parameters on the Params panel, Check the code where bug reported, and the params you input and the Type of parameter in function. This error may be caused by a different params structure, I also update the demo code to make it more straightforward and understandable. you can compare the full code here: https://github.com/AirCodeLabs/aircode/tree/main/examples/blog-subscription-and-pushing or you can simply copy a App from README.md Button "Depoly to AirCode" . feel free to contact me if you still have not solved the problem.

Hey Roy Ibarra There may be some problems with the Fetch header, try adding Content-Type to your fetch request header in src/app/page.tsx, e.g. 'Content-Type': 'application/json', and try again. async function sendRequest ( url: string, { arg }: { arg: { email: string }} ) { return fetch(url, { headers : { 'Content-Type' : 'application/json' }, method : 'POST' , body : JSON .stringify(arg) }).then( res => res.json()) } Thank you for your feedback. I will add a headers and update this part code.

Hi Roy, Kevin Here, copy the SWR request code into src/app/page.tsx file, you can check it out via https://github.com/0xinhua/blog-subscription-form/blob/main/src/app/page.tsx Thanks for your reminding, I have updated this part.

Hey Daniela, Glad you found it valuable. Thanks for reading!