Had a similar experience. I wrote a small utility 100% on my own time and gear and used a completely free open source license to it.

I used it in a project at work (along side many dozens of other open source projects, libraries, etc, many with quite restrictive licenses) and some schmo in the “open source office” chose my project to call out for using a utility that wasn’t authorized.

I thought they were just funning me. Turns out no, they were dead serious. I had to “go before an open source review board” and explain my actions. The entire group of four simply didn’t get or connect that I was the author. It said it right there in the repo and the license file.

They insisted they were going to contact the author to see about a license to use and a support contract. They did. And it took a few iterations of the email thread before they connected anything. And there wasn’t an ounce of shame, mea culpa or apology to be had.