Vent: My own spam filter flagged me for sending 4 emails to my own crew

I run a small landscaping crew in Boise and last month our email provider started blocking my own messages to my guys. I figured the algorithm was just broken, so I sent the same schedule email 9 times in one morning to test it, and every single one bounced back with a warning about "suspicious activity." Turns out the bot was right, sort of, because one of my guys had replied to an old thread and his phone auto forwarded it to 40 people, which made my whole domain look like a spam cannon. I called support and the lady said my account got flagged in under 2 minutes. Honestly I was the skeptical one and the bot was doing its job. Now I'm curious, has anyone else gotten nailed by their own provider over stuff a coworker did?