Why am I getting a JSON error and how do I fix it

I am trying got take the value that is inserted into the first and last name fields and then take that and insert it into a MySQL database backend that I have running using restAPI. I got some help to fix the form but I am trying to find the error when I try to take the input form the form and enter it in the database

The table code is this

  <div class="superhero">
    <h1>Lets add our first name </h1>
    <form action="/add_user" method="post">
        <input type = "text" firstname = "firstname">
    <h1>Lets add our last name </h1>
    <form action="/add_user" method="post">
        <input type = "text" lastname = "lastname">
        <input type="submit" class="btn btn-primary">
    </form>

Then this is taken into the nodeJS server with this command

app.post('/add_people', function(req, res){
    axios.get('http://127.0.0.1:5000/api/adduser')
    .then((response)=>{
        var restlist = response.data.results;
        console.log(restlist);
// Now we will execute the results in the page named thanks
    });
});

Then at the end it is going to be taken to the RestAPI with that is using this route

@app.route('/api/adduser', methods = ['POST']) # This is a post method because the user needs to be able to add info
def adding_stuff():
    request_data = request.get_json() # Gets the info from the table and converts to JSON format
    new_fname = request_data['firstname']
    new_lname = request_data['lastname']
    conn = create_connection("", "", "", "")
    sql = "INSERT INTO restaurantusers (firstname, lastname) VALUES ('%s', '%s');" % (new_fname, new_lname) # This sql statement will then be uploaded to the databse to add a new record
    execute_query(conn, sql) # This will execute the query
    return 'Post worked'

Sorry if what I am asking sounds really complicated. Professor goes too fast in class and I’ve been trying to find out how to do this for sometime with no luck.

UDATE: I later changed the two items as suggested. The route is

app.post('/add_people', function(req, res){
    axios.post('http://127.0.0.1:5000/api/adduser')
    .then((response)=>{
        var restlist = response.data.results;
        console.log(restlist);
// Now we will execute the results in the page named thanks
    });
});

and the form is now

        <form action="/add_people" method="post">
            <input type = "text" firstname = "firstname">
        <h1>Lets add our last name </h1>
            <input type = "text" lastname = "lastname">
            <input type="submit" class="btn btn-primary">
        </form>

I get the error that

  },
  isAxiosError: true,
  toJSON: [Function: toJSON]
}

and also this error on the restAPI window

TypeError: 'NoneType' object is not subscriptable