Unable to get JSON from API server present in Heroku in axios

No'Access-Control-Allow-Origin' header is present on the requested resource.Origin' http://localhost:3001' is there not allowed access.

• Change config when doing axios.get
  

  
  
  constapi_url="https://xxx.herokuapp.com/api/v1 "
  
  const config = {
  
  headers:{'Access-Control-Allow-Origin':'*'}
  
  }
  
  export const readRepositories=()=>async dispatch=>{
  
  const response = wait axios.get(api_url,config);
  
  dispatch({type:READ_REPOSITORIES, response});
  
  }
  
  

• Access the API server directly from your browser
  Successful

constapi_url="https://xxx.herokuapp.com/api/v1 "

const config = {

headers:{'Access-Control-Allow-Origin':'*'}

}

export const readRepositories=()=>async dispatch=>{

const response = wait axios.get(api_url,config);

dispatch({type:READ_REPOSITORIES, response});

}