send_keys() command don't work on python selenium

Question

import time
from tkinter.tix import ButtonBox 
from selenium import webdriver
from selenium.webdriver.common.action_chains import ActionChains
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support.wait import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.by import By

driver = webdriver.Chrome('/Users/ziub1n/Desktop/++/dropY/chromedriver')

url = "https://portal.librus.pl/rodzina"
driver.get(url)
driver.maximize_window()

click = driver.find_element_by_xpath('/html/body/nav/div/div[1]/div/div[2]/a[3]')
click.click()

time.sleep(2)

login = driver.find_element_by_class_name('zmdi-account')
login.click()

This is my problem this column doesn't work.

a = 'Login'
date_element = driver.find_element_by_id(a).send_keys('213123224')