It is possible to go over your BR Campaign Daily Limit. This is due to the way we determine your Verified Orders, and also how your customers enter the Manychat Flow.
For example, you could have a daily limit of 2, but your FB Ad could send in 5 customers. When these 5 customers enter your deal, BR would say you have 0 Verified Orders from your Seller Central so all 5 customers will get in your deal. At some point, all 5 customers will buy your product, and now you have 5 Verified orders, with a Daily Limit of 2. Any new customers will not get in because you are over your limit, but those original 5 have already placed their order.
We cannot deny the 5 customers their rebate because they have already ordered. Denying them could potentially anger them into giving you a 1-star review, and we are avoiding this at all costs.
The solution to managing you Daily Limit is to keep a very close eye on your FB Ad Budget. You want people to trickle into your deal very slowly over the day so only 1 customer at a time gets to buy your product. If your FB Ad Budget is too high, you can send in too many people too quickly, and you would go over your BR Daily Limit.