StaleElementReferenceException Using Selenium in Python

Yes i know that this type of question has been answered many times before, but none of them helped me. Actually i didn't know much about it so need your help!

My problem: I am scraping through a website and it needs a CAPTCHA to search for every input. So i use FireFox as my browser as it asks for the captcha one time and doesn't change it. My code asks the user for CAPTCHA one time and then click on search button and tries to scrape the data, but when it clicks on the search button again (as it is in a loop) then it raises this error:

selenium.common.exceptions.StaleElementReferenceException: 
Message: The element reference of <input id="txt_ALPHA_NUMERIC" class="ui-inputfield ui-inputtext ui-widget ui-state-default ui-corner-all" name="txt_ALPHA_NUMERIC" type="text"> is stale; 
either the element is no longer attached to the DOM, it is not in the current frame context, or the document has been refreshed

My code:

from selenium import webdriver                    # Import module 
from selenium.webdriver.common.by import By
from selenium.webdriver.common.keys import Keys   # For keyboard keys 
import time    
import pandas as pd

URL = 'https://vahan.nic.in/nrservices/faces/user/searchstatus.xhtml'      # Define URL 
browser = webdriver.Firefox(executable_path=r'C:\Users\intel\Downloads\Setups\geckodriver.exe')  

browser.get(URL)

vehicle_no = browser.find_element_by_xpath("""//*[@id="regn_no1_exact"]""")
vehicle_no.send_keys('RJ14CX3238')

captcha_input = input("enter your captcha ")
captcha = browser.find_element_by_xpath("""//*[@id="txt_ALPHA_NUMERIC"]""")
captcha.send_keys(captcha_input)
button_click = browser.find_element_by_xpath("/html/body/form/div[1]/div[3]/div/div[2]/div/div/div[2]/div[5]/div/button/span").click()    

i = 111
attempt = 1
max_attempts = 2
while True: 
    i = i + 1
    time.sleep(4)
    reg_no = browser.find_element_by_xpath("/html/body/form/div[1]/div[3]/div/div[2]/div/div/div[2]/div[6]/div/div/div/table/tbody/tr[2]/td[2]/span").text
    date = browser.find_element_by_xpath("/html/body/form/div[1]/div[3]/div/div[2]/div/div/div[2]/div[6]/div/div/div/table/tbody/tr[2]/td[4]").text 

    vehicle_no = browser.find_element_by_xpath("""//*[@id="regn_no1_exact"]""")
    vehicle_no.send_keys('RJ14CX3' + str(i))

    captcha.send_keys(captcha_input)

    button_click = browser.find_element_by_xpath("/html/body/form/div[1]/div[3]/div/div[2]/div/div/div[2]/div[5]/div/button/span").click()    
    browser.execute_script("return arguments[0].scrollIntoView(true);", button_click)

Also fix any other problems if is in my code. Any help would be appreciated!! Thanks in advance.