WhatsApp account got banned, how do I prevent this again

That sounds rough, when you've got a job riding on staying connected to clients. WhatsApp's automated system is super aggressive about flagging accounts that look like spam, even when you're running legitimate promotions. They watch for patterns like mass messaging, rapid-fire sends to new contacts, or too many people blocking or reporting your number. The problem is their detection doesn't care if you're a real business or some sketchy operation, it just sees the activity volume and drops the hammer. You probably got flagged because sending bulk promos looks identical to spam from their end, even though you're doing authorized company work.