Proxy issue on React app connecting heroku server

Hi Netlify team. I came across one problem after deployment. Problem is proxy not working after deploying my React app in netlify. I am using api deployed in heroku. [https://spis-backend.herokuapp.com]

I am using React v17 currently, and I did proxy from localhost with createProxyMiddleware. I had tried something with __redirect in the build public folder

/api/v1/* https://spis-backend.herokuapp.com/:splat 200
/* /index.html 200

But it does not work.

To get response my api endpoint is like this [https://spis-backend.herokuapp.com/api/v1/login].
So what is wrong with my code? In my browser, api request are bad.
My deployed site is
[https://tuition-system-spis-v2.netlify.app/]

Hi @EuJin03,

What do you mean by API request are bad? I’m getting a 404, is that what you’re talking about?