Python with selenium: unable to locate element which really exist

The problem is that your input tag is inside an iframe, you need to switch to it first:

frame = driver.find_element_by_xpath('//frame[@name="main"]')
driver.switch_to.frame(frame)
pass1 = driver.find_element_by_id("PASSFIELD1")

Add some delay to the driver so that elements will load.

import time
time.sleep(2)
department_element = driver.find_elements_by_id("__id_name__")

or else you can use the following code so that loop runs until the element render

while len(driver.find_elements_by_id("__id_name__")) == 0:
    pass
department_element = driver.find_elements_by_id("__id_name__")