Here are some limits to bear in mind when you create automated rules:

• You can create up to 250 automated rules on a single ad account. This includes active rules and inactive rules.
• You can only add one of each condition per rule.
• You can only associate a single rule with objects on the same level. For example, you could apply a single rule to three campaigns or to three ad sets, but you can't apply a single rule to three campaigns and three ad sets. You should create a rule for your campaigns and another rule for your ad sets instead.

* Nguồn: Facebook