This script
<script type="text/javascript">
$(function() {
$('.send').live('click', 'button', function()
{
var user1 = $(this).val();
var user2=$(this).prev().val();
var text=$(this).prev().prev().val();
var my_data = {
    user1: user1, text:text, user2:user2,
};
console.log(my_data)
$.ajax({
    url: "/updatechat",
    data: my_data,
    type: 'POST',
    success: function(response) {
        console.log(response)
     },
    error: function(error) {
        console.log(error);
    }
});
});
});
is raising an error with the correspondent route /updatechat
@app.route('/updatechat', methods=['GET','POST']) 
def updatechat():
user1 =  request.form['user1']
user2 =  request.form['user2']
text =  request.form['text']
return [user1,user2,text] #not the actual code
but will NOT raise the same error if, in the previous piece of code, i replace with this
user1='bbb'
user2='whatever'
text='idk'
this "var = request.form['var']" form works on several different routes on my code
 
    