Fetch API Returning 304 Not Modified in Angular

Question

I created an Angular frontend and a .Net backend, API call from my Angular client that was initially working has stopped working. The only change I made was change the structure of the object sent to frontend. I have cleared my cache, still issue persist.

fetch(URL) 
  .then(response => response.json())
  .then(data => {

    console.log(data)

})