Bounce back emails

I have a client on mxroute that is complaining about certain people getting bounce backs. How can I make sure nothing is blocking eagle’s mail server or getting flagged by spam?

In this case the most important detail will be why it’s bouncing. Most bounce messages are due to invalid recipient addresses in our experience. Feel free to message me here or on Slack and give me some of the bounce errors you’re receiving (the full headers and body may be helpful).

https://join.slack.com/t/mxroutesupport/shared_invite/enQtNDY1NDI2Mzg2Mjc4LTFhNTM3MTc1OTUzYTU3MjliZDlkYzgwNzE0YzIwMWVmNmJiYTg3YWQ5NGY3YzhiOWMyNTc0MmQ4NjNiNGMzMzg