Login function does not redirection to another html file

My code doesn’t redirect to my other html file and I have no Idea why. The login function works fine but it just doesn’t redirect for some reason.

function login(){
    let username = document.getElementById("user").value;
    let password = document.getElementById("password").value;
    if (checkUser(username,password)){
      window.location.assign("Student.html");
    }
    else if (username =="Admin" && password == 7800){
      location.assign('Librarian.html');
    }
    else {
        alert("Incorrect Username/Password or Not Registered");
    }
}

   <div class="Log">
        <div class="login">
            <form class="needs-validation">
                <h1 class="text-center pt-3"> Log in Form</h1>
                <hr />
                <div class="form-group was-validated">
                    <label class="form-label" for="user">Username</label>
                    <input class="form-control" type="text" id="user" />
                    <div class="invalid-feedback">
                        Invalid Username
                    </div>
                </div>
                <div class="form-group was-validated">
                    <label class="form-label" for="password">Password</label>
                    <input class="form-control" type="password" id="password" />
                    <div class="invalid-feedback">
                        Invalid Password
                    </div>
                    </div>
                    <div class="form-group">
                        <input class="form-check-input" type="checkbox" id="checkRemember" />
                        <label class="form-check-label" for="check">Remember me</label>
                    </div>
                    <button class="btn btn-success w-100 mb-3" id="btn_Log" onclick="login()">Log In</button>
                    <div class="login-register">
                        <p>Don't have an account? <a href="Register.html" class="register-link">Register</a></p>
                    </div>
            </form>
        </div>
    </div>
    <script src="logreg.js"></script>

I have try the different ways to redirect and none of them worked. I don’t know what to do.