input tags in html code change when using selenium

I have been using selenium to try and automate competition entries on Gleam. I had posted a question earlier about problems with finding tags but I eventually got it working by finding the iframe. However, the class tag that I used to enter my FULL_NAME has disappeared and does not exist anymore. It was the only tag that made the input tag unique.

So my question is, are the HTML tags changing when I reload the page? If so, why? and how can I distinguish between input tags when everything about them (i.e. id, name, class etc.) is exactly the same?

Here is my code if anyone wants to try and automate this site:

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

browser = webdriver.Chrome('/Users/<MY_NAME>/Documents/Automate_Login_py/chromedriver')

browser.get(('https://gleam.io/contest/airpods-pro'))

frame= "GleamEmbedzcR0I"
browser.switch_to.frame

# The below @class tag is not showing anymore
enterName = browser.find_element_by_xpath("//input[@class= 'ng-empty ng-invalid ng-invalid-required ng-valid-pattern ng-dirty ng-valid-parse ng-touched']")

enterName.send_keys('John Smith')