We've been a happy SendGrid customer for a couple of years. About 200k emails per month, all transactional emails to/from users of our software. We have 2FA configured and follow all their best practices. Last month their compliance team suspended our account for 6 hours on a Friday with no warning.

I've been talking to their support team for a couple of weeks, and they can't explain why we were suspended. They say that they only suspend accounts for suspicious behavior, but can't tell us why our account looked suspicious or how to prevent the problem from recurring.

Are there any best practices for preventing the "compliance team" from suspending our account? Or strategies for recovering faster? If not, are there any companies like SendGrid with better/faster customer support?