Well don't bot 3-4 hours straight if you never botted on it... the change in behaviour is big if you always played it by hand.
You Have to build it up slowly and take a shitload of breaks.
It's a common misconception that old accounts which never botted before are very safe, well It's exactly the opposite actually.
Accounts that only botted are usually safer to bot on because they use the same playstyle, the game doesn't know another playstyle on that account.