How can I prevent SQL injection in PHP?

Axios PUT to update a Jira issue with Basic auth

Acothley

I have a GET request that returns successfully:

async function getData() {
    try {
      const response = await axios.get(url, {  
        auth: {
            username: {JIRA USER},
            password: {JIRA API KEY}
        }
      });
      console.log(response.status)
      return response.data;
    } catch (error) {
      console.error(error);
    }
  }

getData()
  .then((output) => {
    console.log(output)
  });

Now I would like to PUT with a payload, which I believe should be a fields object, like this:

async function getData() {
    try {
      const response = await axios.put(url, {'fields':{'customfield_XXXXX':'this is an update'}} , {  
        auth: {
            username: {JIRA USER},
            password: {JIRA API KEY}
        }
      });
      console.log(response.status)
      return response.data;
    } catch (error) {
      console.error(error);
    }
  }

However when I run it, I get a bad request error.

I can't understand if it is that I am PUTing incorrect with Axios, or accessing the Jira API incorrectly. I thought that maybe I need to put the body in a different location but the docs and other examples suggest I have in the right place.