Checking for validation using a switch statement

I am trying to set up conditional rendering using in the backend for allowing a user to update their profile. My first thought was to use a switch statement since it is a case by case on what they want to update (username, location, etc.), however I cannot get the validation to work case-by-case. Is there a more efficient way of doing this without using ReactJS? Below is the code and error log. I have removed the “break” clause in order for the switch to keep going in checking for an actual value. I have also tried “.trim().length” as part of the validation but the validation error i posted keeps popping as well.

profile.js

router.post("/update/:id", (req, res) => {
  console.log("UPDATING ROUTE HIT n");

  try {
    console.log("MADE IT INSIDE THE TRY ROUTE n");
    if (req.isAuthenticated()) {
      User.findOne({ id: req.params.id }, (err, foundUser) => {
        if (foundUser) {
          console.log("FOUND USER n");
          const newUpdate = {
            username: req.body.username,
            company: req.body.company,
            location: req.body.location,
            position: req.body.position,
          };
          switch (true) {
            // THIS IS THE PROBLEM
            case newUpdate.username !== "" && newUpdate.username !== User.find({ username: { $ne: null } }):
              foundUser.username = newUpdate["username"];
            case newUpdate.company !== "" && newUpdate.company.length >= 3:
              foundUser.company = newUpdate["company"];
            case newUpdate.location !== "" && newUpdate.location.length >= 3:
              foundUser.location = newUpdate["location"];
            case newUpdate.position !== "" && newUpdate.position.length >= 3:
              foundUser.position = newUpdate["position"];
              break;
            default:
              console.log("FAILED TO ENTER ANYTHING" + err + "n");
              break;
          }
          foundUser.save((err) => {
            if (err) {
              console.log("THERE WAS AN ERROR: " + err + "n");
            } else {
              console.log("SUCCESSFULLY CHANGED POSITION");
            }
          });
          res.redirect("/profile");
        } else {
          console.log("FOUND THE ANSWER" + err + "n");
        }
      });
    }
  } catch (error) {
    console.log("THERE WAS AN ERROR(caught): " + error + "n");
  }
});