Somehow i have just got my 2nd captcha in 24 hrs. It seems to be when i log off of pokefarmer and try to start it back up in the same location later on. All pokestops disappear, i then log into the game on my phone and boom captcha waiting for me.... I have paid for the service from them hours ago shows its active and put the correct API key from them in, seems to not even show it on the screen if i am getting one before logging out or something.