The transport rule can't be created because you've exceeded the maximum number of recipients that can be added to a message ...

The transport rule can't be created because you've exceeded the maximum number of recipients that can be added to a message by all your transport rules. Your transport rules are adding {0} recipients, and the maximum number is {1}. Reduce the number of recipients, either by removing recipients from actions in existing rules, or by removing existing actions that add recipients. Or delete existing transport rules that add recipients.