No text sent to input box using Python

I am trying to send value to an input box but no matter what I have tried, it does not work. I have tried the following ways with the HTML code embedded in this link:

time.sleep(3)
request_title = driver.find_element_by_xpath("//input[@class='proto-input-text connect-text-input__input-field ng-touched ng-dirty ng-valid']").click()
request_title[0].send_keys('Hello')

and

time.sleep(3)
request_title = driver.find_element_by_class_name('proto-input-text connect-text-input__input-field ng-touched ng-dirty ng-valid').click()
request_title[0].send_keys('Hello')

and

time.sleep(3)
driver.find_element_by_xpath("//input[contains(@class, 'proto-input-text connect-text-input__input-field ng-touched ng-dirty ng-valid')]").send_keys('Hello')

But all have return the same error - stating that there is "no such element":

selenium.common.exceptions.NoSuchElementException: Message: no such element: Unable to locate element: {"method":"xpath","selector":"//input[@class='proto-input-text connect-text-input__input-field ng-touched ng-dirty ng-valid']"}

Is there any other configuration to make this work ? ie using CSS or something else ? I am really new into coding and i have no idea how to work on beyond this. I am trying to send "Hello" to an input box, for example.