Why did I receive this error?
Each Buffer account has a limit to how many messages can be scheduled. If you’ve hit that limit, Buffer will refuse to accept the message from CoSchedule, causing a message failure.
What should I do to resolve this?
To correct this, you can upgrade your Buffer account to increase the maximum number of messages that can be scheduled.
How do I prevent this error from happening in the future?
To keep from running into this error only schedule the number of messages allowed with your Buffer account.