How to resolve this Unauthorized request (401 Response)?

Question

I am trying to do some scraping from websites using GET and POST methods, but now I am facing a new challenge.

I am trying to get data from a credit simulator, I found this portuguese site (https://simuladores.bancomontepio.pt/ITSCredit.External/Calculator/ITSCredit.Calculator.UI.External/gateway/Calculator/api/Calculator/Calculate?hash=-1535840118).

As far as I know, I need to use POST method,but I am only getting 401 for the response.

Here is my code:

Any ideas on what the problem is?

from openpyxl import load_workbook
import requests
import numpy as np
import time
from datetime import datetime
import pandas as pd
import json

import warnings
warnings.filterwarnings("ignore")




#O MONTANTE MINIMO A SER FINANCIADO NO MONTEPIO É 2500€
mont_min = 2000
mont_max = 30000
mont_step = 500

prazo_min = 36
prazo_max = 96
prazo_step = 6



response_errors = []


def benchmark(PRAZO, MONTANTE):
    # colunas da tabela final
        columns = ['date','amount','monthly_payment_without_ins','MTIC', 'maturity', 'taeg', 'tan', 'type']
            
        # bancos analisados
        df = pd.DataFrame(np.nan, index=['Montepio'], columns=columns)
            
            
        pd.set_option('display.max_columns', 10)
            
        #    aux_MONTANTE = (str('{:0,.0f}'.format(MONTANTE)) + " €").replace(",", ".")
        #    aux_PRAZO = str(PRAZO) + " meses"
            
            
            
        url_Montepio = 'https://simuladores.bancomontepio.pt/ITSCredit.External/Calculator/ITSCredit.Calculator.UI.External/gateway/Calculator/api/Calculator/Calculate?hash=-1535840118'

       
        headers_Montepio = {'Accept': 'application/json, text/plain, */*',
                            'Accept-Encoding': 'gzip, deflate, br',
                            'Accept-Language':'pt-PT,pt;q=0.9,en-US;q=0.8,en;q=0.7',
                            'Connection': 'keep-alive',
                            'Content-Length': '969',
                            'content-type': 'text/plain',
                            'Cookie': 'OptanonAlertBoxClosed=2023-02-15T13:57:43.951Z; _gcl_au=1.1.776232285.1676469471; ASP.NET_SessionId=5ggffmgwygzrqhda0ufmdgip; _ga=GA1.2.829667105.1676469478; _gid=GA1.2.888620949.1678890412; calc-cookie=; _ga_8WVEJF7X11=GS1.1.1678890400.2.0.1678890496.60.0.0; _gat=1; OptanonConsent=isGpcEnabled=0&datestamp=Wed+Mar+15+2023+14%3A28%3A18+GMT%2B0000+(Hora+padr%C3%A3o+da+Europa+Ocidental)&version=6.38.0&isIABGlobal=false&hosts=&consentId=a56ebf5e-f207-48ad-90a4-746316bbace0&interactionCount=1&landingPath=NotLandingPage&groups=C0001%3A1%2CC0002%3A0%2CC0003%3A0%2CC0004%3A0&geolocation=ES%3BMD&AwaitingReconsent=false; _gat_UA-186811106-6=1; _gali=sliderAmount',
                            'Host': 'simuladores.bancomontepio.pt',
                            'Origin': 'https://simuladores.bancomontepio.pt',
                            'Referer': 'https://simuladores.bancomontepio.pt/',
                            'sec-ch-ua': '"Google Chrome";v="107", "Chromium";v="107", "Not=A?Brand";v="24"',
                            'sec-ch-ua-mobile': '?0',
                            'sec-ch-ua-platform': '"Windows"',
                            'Sec-Fetch-Dest': 'empty',
                            'Sec-Fetch-Mode': 'cors',
                            'Sec-Fetch-Site': 'same-origin',
                            'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36'}
        
        
        
        payload_Montepio = {"CCRDCalculateInput":{},"MultifunctionsCalculateInput":{},
 "Device":
     {"Browser":"chrome",
      "BrowserVersion":"107.0.0.0",
      "Device":"Desktop",
      "Os":"windows",
      "OsVersion":"windows-10",
      "UserAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36"},
      "IsCustomer":"true",
      "Ammount":3500,
      "Term":36,
      "ConditionCode":"26BU199902X-01-I-199902-F",
      "CreditDestinationCode":"199902",
      "ProductCode":"26BU199902X",
      "FinancedExpenses":"false",
      "FrequencyTrancheCode":"null",
      "GoalCode":"E001",
      "GoalDescription":"EQUIPAMENTO ENERGIAS RENOVÁVEIS",
      "FrequencyTypeCode":"M",
      "FamilyCode":"CP",
      "Proponents":
          [{"Position":1,
            "Birthday":"1993-03-15T13:28:18.000Z",
            "State":"true",
            "EntityType"
            :{"ID":1,
              "CompanyID":1,
              "Code":"P",
              "Description":"Proponente",
              "Value":"null",
              "ValueString":"null",
              "State":"true",
              "Imported":"null"},
            "ExpenseCodes":["009"]}],
          "ResidualValue":0,
          "InterestOnly":0,
          "Deferment":0,
          "OptionalExpenses":
              [{"Code":"009",
                "Factor":1}],
              "Counterparts":0}
           
        
        
        response_Montepio = requests.post(url_Montepio, headers=headers_Montepio, data=payload_Montepio, verify=False).json()

Any ideas on what the problem is?