I'm doing a basic request to a backend in JS (only to check a user instance exists and will return a bool (true/false) to prevent returning full user data until needed)

From what I have been told by peers it's ill-advised to be passing sensitive data (in this case people's emails) via paths and should be via the body (I haven't looked into why) Anyway, so the way I configured it was to be contained within the body like this:

GET http://localhost:8080/User/check
Content-Type: application/json
{
  "email" : "B.Nye@ABC.uk"
}

However when doing this call in JS:

  if (isAuthenticated){
    console.log("test -----------")
    console.log(user.email)
    fetch("http://###.###.###.###:8080/User/check", {
       method: "GET", 
       headers:{"Content-Type":"application/json"},
       body: JSON.stringify( {
          email: "B.Nye@ABC.uk"
       })
       
  }).then((result)=> {
    if (result.ok){
      console.log("sucess")
    }
    else{
      console.log("fail")
  }})}

I get this error:

Unhandled Rejection (TypeError): Failed to execute 'fetch' on 'Window': Request with GET/HEAD method cannot have body.

Is there a way to bypass this or am I restricted to using either a POST method and reworking my backend method or containing the users email inside of the path?