Someone is sending messages from your business email address
If the wrong person is able to send emails with your email address, they can ask your suppliers and customers to do all sorts of things by impersonating you. It can be trivial for hackers to send email as you or anyone in your business if you haven't taken a few important steps to make sure no one but you can act as you.
How could this happen?
Some of the most common ways small business email accounts are hacked.
How could this harm us?
Your business could be impacted if someone start sending messages from your email accounts.