The bot started when a customer only replied to a message we sent. How do I avoid that?
Keep "Flows do not start on a reply to your team" on (default): a reply within 72 hours of a human message is not a new conversation.
Leave the flow option Flows do not start on a reply to your team on; it is on by default, with a window of 72 hours that you can change. When the newest outgoing message to that customer on that number was written by a person, an incoming message inside the window is treated as a reply to your team, not as a new conversation, and the flow stays quiet.
What counts as "written by a person": a message from WASync Chat, from the WhatsApp tab on a record, from the Open Channel, or typed on the company phone. What does not count: the bot's own messages, robots, automations and the inactivity reminders. So a customer who answers your bot late still gets a fresh run, while a customer who answers your colleague does not get greeted by a bot.